KR20170105019A - Surface protecting film and optical member - Google Patents

Abstract

A surface protective film and an optical member capable of achieving an antistatic property and a temporal stability of a peeling electrification voltage are provided. The surface protective film of the present invention comprises a substrate having a first side and a second side, an antistatic layer provided on the first side of the substrate, and a pressure-sensitive adhesive layer formed on the second side of the substrate with a pressure- Wherein the antistatic layer is formed of an antistatic agent composition containing a polythiophene doped with a polyaniline sulfonic acid and a polyanion as a conductive polymer component and a binder, wherein the polyaniline sulfonic acid and the polyanion (Mass ratio) of the polythiophenes doped by the polythiophenes is in the range of 90:10 to 10:90.

Description

Surface protecting film and optical member

The present invention relates to a surface protective film and an optical member.

The present invention relates to a surface protective film comprising a substrate having a first surface and a second surface, an antistatic layer formed on the first surface of the substrate, and a pressure-sensitive adhesive layer formed on the second surface of the substrate, To a surface protective film having an antistatic function. The surface protective film according to the present invention is suitable for application to a plastic product which is likely to generate static electricity. Among them, particularly useful as a surface protective film for protecting the surface of an optical member (for example, a polarizing plate, a wave plate, a retardation plate, an optical compensation film, a reflection sheet, a brightness enhancement film used for a liquid crystal display or the like) Do.

The surface protective film (also referred to as a surface protective sheet) generally has a constitution in which a pressure-sensitive adhesive layer is formed on a film-like base material (support). Such a protective film is bonded (adhered) to an adherend (subject to be protected) through the pressure-sensitive adhesive layer, thereby protecting the adherend from damage or contamination during processing and transportation. For example, a panel of a liquid crystal display is formed by bonding an optical member such as a polarizing plate or a wave plate to a liquid crystal cell via a pressure-sensitive adhesive layer. In the manufacture of such a liquid crystal display panel, a polarizing plate to be adhered to a liquid crystal cell is once formed into a roll form, then cut out from the roll and cut into a desired size according to the shape of the liquid crystal cell. In order to prevent the polarizing plate from being damaged due to the conveying roll or the like in the intermediate process, countermeasures have been taken to apply the surface protective film to one side or both sides (typically, one side) of the polarizing plate. The surface protective film is peeled off at a stage where it is no longer needed.

Generally, since the surface protective film or optical member is made of a plastic material, the electrical insulation is high, and static electricity is generated by friction or peeling. Therefore, when the surface protective film is peeled off from the optical member such as the polarizing plate, static electricity is likely to be generated. When voltage is applied to the liquid crystal in the state where the static electricity remains, the orientation of the liquid crystal molecules may be lost, . In addition, the presence of static electricity may be a cause of sucking dust or lowering workability. For this reason, antistatic treatment has been carried out on the surface protective film. For example, by forming the antistatic layer or the antistatic coating as the surface layer (top coat layer, back surface layer) of the surface protective film, (See Patent Document 1).

In recent years, as a conductive polymer used for imparting an antistatic function to the surface layer of a surface protective film, there has been proposed a poly (3,4-ethylenedioxythiophene) / PSS (polystyrenesulfonic acid) However, when the antistatic layer is formed using the conductive polymer, the PSS (corresponding to the dopant) is released from the PEDOT over time and the surface resistivity and the peeling electrification voltage are increased (Deterioration) of the surface resistivity occurs, there is a possibility that when the surface protective film is peeled off from the adherend, static electricity There is a fear of occurrence of a problem.

Patent Document 1: JP-A-2008-255332

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a surface protective film and an optical member capable of achieving antistatic properties and time-lapse stability of peeling electrification as a result of intensive studies in view of the above circumstances.

That is, the surface protective film of the present invention comprises a substrate having a first surface and a second surface, an antistatic layer formed on the first surface of the substrate, and a pressure-sensitive adhesive layer formed on the second surface of the substrate with a pressure- Wherein the antistatic layer is formed from an antistatic agent composition containing a polythiophene doped with a polyaniline sulfonic acid and a polyanion as a conductive polymer component and a binder, wherein the polyaniline sulfonic acid and the polyanion (Mass ratio) of the polythiophenes doped by the polyisocyanate is 90: 10 to 10: 90.

In the surface protective film of the present invention, it is preferable that the polythiophene is poly (3,4-ethylenedioxythiophene) (PEDOT).

In the surface protective film of the present invention, it is preferable that the polyanions are polystyrene sulfonic acid (PSS).

In the surface protective film of the present invention, it is preferable that the binder is a polyester resin.

In the surface protective film of the present invention, it is preferable that the antistatic agent composition includes a melamine crosslinking agent and / or an isocyanate crosslinking agent as a crosslinking agent.

In the surface protective film of the present invention, the antistatic agent composition preferably contains at least one member selected from the group consisting of a fatty acid amide, a fatty acid ester, a silicone lubricant, a fluorine lubricant, and a wax lubricant as a lubricant.

In the surface protective film of the present invention, it is preferable that the substrate is a polyester film.

In the surface protective film of the present invention, it is preferable that the pressure-sensitive adhesive composition contains at least one kind selected from the group consisting of an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, and a silicone pressure-sensitive adhesive.

In the surface protective film of the present invention, it is preferable that the pressure-sensitive adhesive composition contains a polyether compound.

In the surface protective film of the present invention, it is preferable that the pressure-sensitive adhesive composition contains an antistatic component.

The optical member of the present invention is preferably protected by the surface protective film.

In the surface protective film of the present invention, the antistatic layer formed on the first surface (back surface) of the substrate is formed from an antistatic agent composition containing a specific proportion of a specific conductive polymer component, And a surface protective film and an optical member which can attain the time-lapse stability of the peeling electrification voltage can be provided.

1 is a schematic cross-sectional view showing an example of the structure of a surface protective film according to the present invention.
2 is an explanatory diagram showing a method of measuring the peeling electrification voltage.

Hereinafter, embodiments of the present invention will be described in detail.

<Overall Structure of Surface Protective Film>

The surface protective film disclosed herein is generally called a pressure-sensitive adhesive sheet, an adhesive tape, an adhesive label, an adhesive film, and the like. Particularly, an optical component (for example, a polarizing plate, Is used as a surface protective film for protecting the surface of an optical component during processing or transportation of the optical component. The pressure-sensitive adhesive layer in the surface protective film is typically formed continuously, but the pressure-sensitive adhesive layer is not limited to such a form, but may be a pressure-sensitive adhesive layer formed in a regular or random pattern such as a dot shape or a stripe shape. The surface protective film disclosed herein may be in the form of a roll or a sheet.

A typical configuration example of the surface protective film disclosed here is schematically shown in Fig. This surface protective film 1 comprises a substrate 12 (for example, a polyester film) 12, an antistatic layer 11 formed on the first surface 12, and a second surface (antistatic layer And a pressure-sensitive adhesive layer (13) formed on the surface opposite to the pressure-sensitive adhesive layer (11). The surface protective film 1 is used by attaching the pressure sensitive adhesive layer 13 to an adherend (protection object, for example, a surface of an optical component such as a polarizing plate). The surface protective film 1 before use (that is, before the application to the adherend) is peeled off when the surface (adhered surface to the adherend) of the pressure sensitive adhesive layer 13 is peeled off at least on the pressure sensitive adhesive layer 13 side Or may be in a form protected by a liner. Alternatively, the surface protective film 1 may be rolled so that the pressure sensitive adhesive layer 13 is in contact with the back surface (the surface of the antistatic layer 11) of the substrate 12 to protect the surface thereof.

The antistatic layer 11 is formed directly on the first surface of the substrate 12 (without interposing another layer), and the antistatic layer 11 is formed on the back surface of the surface protective film 1 (In other words, the antistatic layer 11 also serves as the top coat layer) is different from the constitution in which the antistatic layer is formed separately from the top coat layer, Since the number of the layers constituting the surface protective film can be reduced, the prevention layer attachment film (and furthermore, the surface protection film using the film) is advantageous from the viewpoint of productivity improvement and the like.

<Description>

The surface protective film of the present invention is characterized by having a substrate having a first side (back side) and a second side (side opposite to the first side). In the techniques disclosed herein, the resin material constituting the base material can be used without particular limitation, and for example, a resin material having excellent properties such as transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, flexibility and dimensional stability is used . Particularly, since the base material has flexibility, the pressure-sensitive adhesive composition can be applied by a roll coater or the like, and it can be wound in a roll form, which is useful.

As the substrate (support), for example, polyester-based polymers such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN) and polybutylene terephthalate; Cellulosic polymers such as diacetylcellulose, triacetylcellulose and the like; Polycarbonate-based polymers; Acrylic polymers such as polymethyl methacrylate; Or the like as a main resin component (a main component in a resin component, typically a component occupying 50 mass% or more) can be preferably used as the base material. Other examples of the resin material include styrene-based polymers such as polystyrene and acrylonitrile-styrene copolymer; Olefin polymers such as polyethylene, polypropylene, polyolefins having a ring or norbornene structure, and ethylene-propylene copolymers; Vinyl chloride-based polymers; Amide polymers such as nylon 6, nylon 6,6, and aromatic polyamide; And the like as a resin material. As another example of the resin material, an imide polymer, a sulfon polymer, a polyether sulfone polymer, a polyether ether ketone polymer, a polyphenylene sulfide polymer, a vinyl alcohol polymer, a vinylidene chloride polymer, Based polymer, an aryl-based polymer, a polyoxymethylene-based polymer, and an epoxy-based polymer. Or a mixture of two or more of the above-mentioned polymers.

As the base material, a plastic film made of a transparent thermoplastic resin material can be preferably employed. Of the above plastic films, a polyester film is more preferable. Here, the polyester film refers to a polymer material (polyester resin) having a main skeleton based on an ester bond such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or polybutylene terephthalate as a main resin component . Such a polyester film has desirable properties as a base material for a surface protective film, such as excellent optical properties and dimensional stability, and has properties that are easily converted into the same.

Various additives such as antioxidants, ultraviolet absorbers, plasticizers, coloring agents (pigments, dyes, etc.), antistatic agents and antiblocking agents may be added to the resin material constituting the substrate. The surface of the polyester film on the side where the antistatic layer is to be formed is subjected to various treatments such as corona discharge treatment, plasma treatment, ultraviolet ray irradiation treatment, acid treatment, alkali treatment, application of an undercoating agent, , Or a surface treatment of known or common use may be carried out. Such a surface treatment may be, for example, a treatment for enhancing the adhesion between the substrate and the antistatic layer. The surface treatment can be preferably employed such that a polar group such as a hydroxyl group is introduced on the surface of the substrate. The same surface treatment as described above may be applied to the second surface (the surface on the side where the pressure-sensitive adhesive layer is formed) of the substrate. Such a surface treatment may be a treatment for enhancing the adhesion between the film and the pressure-sensitive adhesive layer (anchoring property of the pressure-sensitive adhesive layer).

The surface protective film of the present invention has an antistatic function by having an antistatic layer on the base material, but it is also possible to use a plastic film that has been subjected to antistatic treatment as the base material. Use of the above-described substrate is preferable because the surface protective film itself is prevented from being charged when peeled off. In addition, when the base material is a plastic film and the plastic film is subjected to the antistatic treatment, it is possible to reduce the electrification of the surface protective film itself and to obtain an excellent antistatic function to the adherend. As a method of imparting the antistatic function, there is no particular limitation, and conventionally known methods can be used. For example, an antistatic resin or a conductive polymer composed of an antistatic agent and a resin component, a conductive resin containing a conductive substance A method of depositing or plating a conductive material, a method of mixing an antistatic agent and the like, and the like.

The thickness of the substrate is usually 5 to 200 占 퐉, preferably 10 to 150 占 퐉. When the thickness of the base material is within the above range, it is preferable that the bonding operation to the adherend and the peeling workability from the adherend are excellent.

&Lt; Antistatic layer (top coat layer) >

The surface protective film of the present invention comprises a substrate having a first surface (back surface) and a second surface (surface opposite to the first surface), an antistatic layer formed on the first surface (back surface) of the substrate, Wherein the antistatic layer comprises a polythiophene which is doped with a polyaniline sulfonic acid and a polyanion as a conductive polymer component, and a pressure-sensitive adhesive layer formed by a binder (Mass ratio) of the polyaniline sulfonic acid to the polythiophene doped with the polyanions is in the range of 90:10 to 10:90. When the surface protective film has an antistatic layer (top coat layer), the antistatic property of the surface protective film and the time-course stability of the peeling electrification voltage are improved, which is a preferable form. Particularly, by mixing the polyaniline sulfonic acid and the polythiophene doped with the polyanions, within the above range, the polyaniline sulfonic acid alone or the polythiophenes doped with the polyanions can be blended alone The time-course stability of the antistatic property is improved, but the following reasons can be inferred. The polythiophenes doped with polyanions form a complex to form an anionic group of polyanions in the polythiophene. The conductive mechanism of the polythiophene is an intramolecular challenge of the polythiophene occurring in the complex, The challenges between the intermolecular challenges of the pentene and the complex structure are known. Here, the conductivity between complex structures is a rate-limiting process because the intermolecular distance is small. Generally, by using polyaniline sulfonic acid, which is higher than polythiophenes, in combination, polyaniline sulfonic acid bonds between polythiophenes and polyanion complexes, and since the polyaniline sulfonic acid itself has conductivity, the conductivity between the composites is increased, It is presumed that the improvement and the stability are increased, and they are very useful as a surface protective film.

&Lt; Conductive polymer &

The antistatic layer is characterized by containing, as a conductive polymer component, polyaniline sulfonic acid and polythiophenes doped with polyanions. By the combination of the conductive polymers, polyaniline sulfonic acid is responsible for the conductivity between the composite structures of the polythiophenes / polyanions, so that the conductivity is higher and the antistatic property based on the antistatic layer and the time It becomes useful to stabilize the transient peeling electrification voltage.

The amount of the conductive polymer to be used is preferably from 1 to 1000 parts by mass, more preferably from 5 to 750 parts by mass, and still more preferably from 10 to 500 parts by mass, relative to 100 parts by mass of the binder contained in the antistatic layer (top coat layer) Wealth. If the amount of the conductive polymer used is too small, the antistatic effect may be small. If the amount of the conductive polymer is too large, the adhesion of the antistatic layer to the base material may deteriorate or the transparency may deteriorate.

The polyaniline sulfonic acid used as the conductive polymer component preferably has a weight average molecular weight (Mw) in terms of polystyrene of 5 10 ⁵ or less, and more preferably 3 10 ⁵ or less. The weight average molecular weight of these conductive polymers is preferably 1 x 10 ³ or more, and more preferably 5 x 10 ³ or more.

As a commercially available product of the polyaniline sulfonic acid, trade name "aqua-PASS" manufactured by Mitsubishi Rayon Co., Ltd. and the like are exemplified.

Examples of the polythiophenes used as the conductive polymer component include polythiophenes such as polythiophene, poly (3-methylthiophene), poly (3-ethylthiophene) (3-butylthiophene), poly (3-decylthiophene), poly (3-hexylthiophene) Poly (3-chlorothiophene), poly (3-iodothiophene), poly (3-cyanothiophene), poly (3-hydroxythiophene), poly (3-methoxythiophene), poly (3-methoxythiophene) (3-ethoxythiophene), poly (3-butoxythiophene), poly (3-hexyloxythiophene) (3-octadecyloxythiophene), poly (3,4-dihydroxythiophene), poly (3,4-dimethoxyophene) Poly (3,4-dibutoxy thiophene), poly (3,4-diethoxythiophene), poly Poly (3,4-dioctyloxythiophene), poly (3,4-dideoxylthiophene), poly (3,4-dipentyloxythiophene) , Poly (3,4-ethylenedioxythiophene), poly (3,4-propylene dioxythiophene), poly (3,4-butenedioxythiophene) , Poly (3-methyl-4-carboxyethylthiophene), poly (3-methyl-4-ethoxythiophene) (3-methyl-4-carboxybutylthiophene). These may be used singly or in combination of two or more. Particularly, from the viewpoint of conductivity, poly (3,4- (PEDOT) is preferred.

The degree of polymerization of the polythiophenes is preferably from 2 to 1000, more preferably from 5 to 100. If it is within the above range, it is preferable because it is excellent in conductivity.

The polyanions are polymers of constituent units having anionic groups, and act as dopants for polythiophenes. Examples of the polyanions include polystyrenesulfonic acid, polyvinylsulfonic acid, polyarylsulfonic acid, polyacrylosulfonic acid, polymethacrylosulfonic acid, poly (2-acrylamide-2-methylpropanesulfonic acid), polyisoprenesulfonic acid, Poly (2-acrylamido-2-methoxyphenyl) methacrylate, poly (4-sulfobutyl methacrylate), polymethallyloxybenzenesulfonic acid, polyvinylcarboxylic acid, polystyrenecarboxylic acid, polyarylcarboxylic acid, polyacrylic carboxylic acid, polymethacrylic carboxylic acid, -Methylpropanecarboxylic acid), polyisoprenecarboxylic acid, polyacrylic acid, and polysulfonated phenylacetylene. These may be homopolymers or copolymers of two or more. Among them, polystyrene sulfonic acid (PSS) is preferable from the viewpoint of improving the conductivity and dispersibility of the polythiophenes.

The polyanions have a weight average molecular weight (Mw) of preferably 1,000 to 1,000,000, more preferably 2,000 to 500,000. Within this range, it is preferable since doping and dispersibility into polythiophene are excellent.

Examples of commercially available products of the polythiophenes doped with the polyanions include polytetrafluoroethylene (PEDOT / PSS) such as trade name "Bytron P" from BAYER, polytetrafluoroethylene Trade name &quot; SEPLE JIDA &quot;, trade name &quot; Vera Sol &quot;, manufactured by Soken Chemical &amp;

The antistatic agent composition preferably has a composition ratio (weight ratio) of the polyaniline sulfonic acid to the polythiophene doped with the polyanions (polyaniline sulfonic acid: polythiophenes doped with the polyanions) of 90: 10 to 10:90, preferably 85:15 to 15:85, and more preferably 80:20 to 20:80. Within the above range, the surface resistivity can be suppressed, and particularly, the stability of the surface resistivity over time is excellent, which is a preferable form. In the case of the polyaniline sulfonic acid alone, since the initial conductivity is low, an increase in peeling electrification voltage and surface resistivity over time tends to easily occur. In the case of the polythiophene alone doped with the polyanion sulfonic acid, The conductivity is high but the polyanion (corresponding to the dopant) is likely to be desorbed from the polythiophene over time, which is not preferable because the peeling electrification voltage and the surface resistivity increase with time.

<Binder>

The antistatic layer is characterized in that it contains a binder for imparting solvent resistance, mechanical strength and thermal stability. As the binder, an acrylic resin, an acrylic urethane resin, an acryl-styrene resin, an acrylic silicone resin, a silicone resin, a fluororesin, a styrene resin, a polyester resin, an alkyd resin, a polyurethane resin, an amide resin, a polyolefin resin, And their modified or copolymer resins. These resins may be used alone or in combination of two or more. Of these resins, polyester resins are preferably used because of their excellent solvent resistance.

The polyester resin is preferably a resin material containing a polyester as a main component (typically 50 mass% or more, preferably 75 mass% or more, for example, 90 mass% or more). The polyester is typically one or two kinds selected from polyvalent carboxylic acids (typically dicarboxylic acids) having two or more carboxyl groups in one molecule and derivatives thereof (anhydrides, esters, halides, etc. of the polyvalent carboxylic acids) It is preferable to have a structure in which one or more compounds (polyhydric alcohol component) selected from the above-mentioned compounds (polyvalent carboxylic acid component) and polyhydric alcohols having two or more hydroxyl groups in one molecule (typically, diols) Do.

Examples of compounds usable as the polyvalent carboxylic acid component include oxalic acid, malonic acid, difluoromalonic acid, alkylmalonic acid, succinic acid, tetrafluorosuccinic acid, alkylsuccinic acid, (±) , Maleic acid, methylmaleic acid, fumaric acid, methylfumaric acid, acetylenedicarboxylic acid, glutaric acid, hexafluoroglutaric acid, methylglutaric acid, glutaconic acid, adipic acid, dithiadipic acid, methyladipic acid , Dimethyladipic acid, tetramethyladipic acid, methylene adipic acid, muconic acid, galactanoic acid, pimeric acid, suberic acid, perfluorosuberic acid, 3,3,6,6-tetramethylsuberine Aliphatic dicarboxylic acids such as acid, azelaic acid, sebacic acid, perfluorosevacic acid, brassylic acid, dodecyldicarboxylic acid, tridecyldicarboxylic acid and tetradecyldicarboxylic acid; Cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,4- (2-norbornene) dicarboxylic acid, 5-norbornene- Alicyclic dicarboxylic acids such as dicarboxylic acid (hydamic acid), adamantanedicarboxylic acid, and spiroheptanedicarboxylic acid; There is provided a process for producing an aromatic polycarbonate resin composition comprising a polycondensation reaction of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product of a polycondensation product, Anthracene dicarboxylic acid, biphenyl dicarboxylic acid, biphenylene dicarboxylic acid, dimethyl biphenylene dicarboxylic acid, 4,4'-p-terphenylenedicarboxylic acid, 4,4'-p-quinolediphenyl dicarboxylic acid, , Naphthalene dicarboxylic acid, naphthalene dicopropionic acid, biphenyl diacetic acid, biphenyl dicopropionic acid, 3,3 '- [4,4' - (methylene di-p-toluenesulfonic acid, -Biphenylene) diphopropionic acid, 4,4'-bibenzyl di acetic acid, 3,3 '(4,4'-bibenzyl) dipropionic acid, and oxydip- Dicarboxylic acids; An acid anhydride of any one of the polyvalent carboxylic acids described above; Esters of any of the above-described polyvalent carboxylic acids (which may be, for example, alkyl esters, monoesters, diesters, etc.); An acid halide corresponding to any of the above-mentioned polyvalent carboxylic acids (e.g., dicarboxylic acid chloride); And the like.

Examples of suitable examples of the polyvalent carboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and acid anhydrides thereof; Aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, succinic acid, fumaric acid, maleic acid, hy- phamic acid and 1,4-cyclohexanedicarboxylic acid, and acid anhydrides thereof; And lower alkyl esters of the dicarboxylic acids (for example, esters with monoalcohols having 1 to 3 carbon atoms).

Examples of the compound that can be employed as the polyhydric alcohol component include ethylene glycol, propylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol , 1,5-pentanediol, 1,6-hexanediol, 3-methylpentanediol, diethylene glycol, 1,4-cyclohexanedimethanol, 3-methyl- Butyl-2-ethyl-1,3-propanediol, xylylene glycol, hydrogenated bisphenol A, bisphenol A And the like. Other examples include alkylene oxide adducts of these compounds (e.g., ethylene oxide adducts, propylene oxide adducts, etc.).

The molecular weight of the polyester resin is a number average molecular weight (Mn) in terms of standard polystyrene measured by gel permeation chromatography (GPC), and is, for example, about 1 × 10 ³ to 1.5 × 10 ⁵ May be about 1 x 10 ³ to about 6 x 10 ⁴ ). The glass transition temperature (Tg) of the polyester resin may be, for example, 0 to 120 캜 (preferably 10 to 80 캜).

Examples of the polyester resin include polyvinyl chloride resins such as Vylonal MD-1100, MD-1200, MD-1245, MD-1335, MD-1480, MD-1500, MD-1930, MD- -2000, trade name of Pluscoat Z-221, Z-446, Z-561, Z-565, Z-880, Z-3310, RZ-105, RZ-570, Z-730, Z-760 And Z-592, Z-687, Z-690, Pesresin A-110, A-120, A-124GP, A-125S, A-160P, A-520, A-613D, , A-640, A-645GH, A-647GEX, A-680, A-684G, WAC-14 and WAC-17XC.

The antistatic layer (top coat layer) may contain a resin other than the polyester resin (for example, a resin other than a polyester resin) as the binder , Acrylic resins, acrylic urethane resins, acrylic styrene resins, acrylic silicone resins, silicone resins, fluororesins, styrene resins, alkyd resins, polyurethane resins, amide resins, polyolefin resins and polysilazane resins, And one or more kinds of resins selected from the group consisting of (meth) acrylate and (meth) acrylate. As a preferred form of the technique disclosed herein, there is a case where the binder of the antistatic layer is substantially composed of only a polyester resin. For example, an antistatic layer having a proportion of the polyester resin in the binder of 98 to 100% by mass is preferable. The proportion of the binder in the antistatic layer as a whole can be, for example, 50 to 95% by mass, and is usually 60 to 90% by mass.

&Lt; lubricant >

The antistatic layer (top coat layer) in the technique disclosed herein is preferably a lubricant which is at least one selected from the group consisting of fatty acid amide, fatty acid ester, silicone lubricant, fluorine lubricant and wax lubricant. By using the lubricant, even in a form in which the surface of the antistatic layer is not subjected to a further peeling treatment (for example, a treatment for applying and drying a known peeling agent such as a silicone-based releasing agent or a long-chain alkyl releasing agent) is not performed, slipperiness ) And printing adhesion can be obtained, which is a desirable form. The form in which no additional peeling treatment is applied to the surface of the antistatic layer in this manner is advantageous in that it is possible to prevent whitening due to the peeling treatment agent (for example, whitening phenomenon by being stored under heating and humid conditions) desirable. It is also advantageous in terms of solvent resistance.

Specific examples of the fatty acid amide include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, hydroxystearic acid amide, oleic acid amide, erucic acid amide, N-oleyl palmitic acid amide, Stearyl amide, N-stearyl stearamide, N-stearyl erucic acid amide, methylol stearic acid amide, methylene bisstearic acid amide, ethylene biscarboxylic acid amide, ethylene bis [0033] The polyamide resin of the present invention is preferably selected from the group consisting of acid amide, ethylene bisstearic acid amide, ethylene bishydroxystearic acid amide, ethylene bisbehenic acid amide, hexamethylene bisstearic acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, - distearyl diphosphoric acid amide, N, N'-distearyl sebacic acid amide, ethylene bis oleic acid amide, ethylene bis Lauric acid amide, m-xylylene bis-stearic acid amide, m-xylylene bis-hydrate, m-xylylene bisamide, N, N'-stearyl isophthalic acid amide, and the like. These lubricants may be used singly or in combination of two or more kinds.

Specific examples of the fatty acid esters include polyoxyethylene bisphenol A lauric acid ester, butyl stearate, 2-ethylhexyl palmitate, 2-ethylhexyl stearate, behenic acid monoglyceride, cetyl 2-ethylhexanoate, Isostearic acid isopropyl palmitate, cholesteryl isostearate, lauryl methacrylate, methyl coconut fatty acid methyl, methyl laurate, methyl oleate, methyl stearate, myristyl myristate, octyl myristate Dodecyl pentaerythritol monooleate, pentaerythritol monostearate, pentaerythritol tetrapalmitate, stearyl stearate, isotridecyl stearate, 2-ethylhexanoic acid triglyceride, butyl laurate, octyl oleate, . These lubricants may be used singly or in combination of two or more kinds.

Specific examples of the silicone-based lubricant include polydimethylsiloxane, polyether-modified polydimethylsiloxane, amino-modified polydimethylsiloxane, epoxy-modified polydimethylsiloxane, carbinol-modified polydimethylsiloxane, mercapto-modified polydimethylsiloxane, , Methylhydrogen silicone, methacrylic modified polydimethylsiloxane, phenol modified polydimethylsiloxane, silanol modified polydimethylsiloxane, aralkyl modified polydimethylsiloxane, fluoroalkyl modified polydimethylsiloxane, long chain alkyl modified polydimethylsiloxane, higher fatty acid Modified ester-modified polydimethylsiloxane, higher fatty acid amide-modified polydimethylsiloxane, and phenyl-modified polydimethylsiloxane. These lubricants may be used singly or in combination of two or more kinds.

Specific examples of the fluorine-containing lubricant include a perfluoroalkane, a perfluorocarboxylic acid ester, a fluorine-containing block copolymer, and a polyether polymer having an alkyl fluoride group. These lubricants may be used singly or in combination of two or more kinds.

Specific examples of the wax-based lubricants include petroleum waxes (such as paraffin wax), vegetable waxes (such as carnauba wax), mineral waxes (such as montan wax), higher fatty acids (such as sertinic acid), triglycerides And the like). These lubricants may be used singly or in combination of two or more kinds.

The proportion of the lubricant in the entire antistatic layer may be 1 to 50% by mass, and usually 5 to 40% by mass. If the content of the lubricant is too small, slipperiness tends to be lowered. If the content of the lubricant is excessively large, the printing adhesion and the back surface peeling force may be deteriorated.

<Cross-linking agent>

The antistatic layer preferably contains at least one member selected from the group consisting of a silane coupling agent, an epoxy crosslinking agent, a melamine crosslinking agent, and an isocyanate crosslinking agent as the crosslinking agent, and more preferably the melamine crosslinking agent and / Or an isocyanate-based cross-linking agent. It is possible to fix the polythiophene doped with polyaniline sulfonic acid and polyanions in the binder in the conductive polymer component which is an essential component in forming the antistatic layer, and is excellent in water resistance, solvent resistance, And the like can be realized. In particular, use of a melamine-based crosslinking agent improves water resistance and solvent resistance, and use of an isocyanate-based crosslinking agent improves water resistance and printing adhesion. When these crosslinking agents are used in combination, water resistance, solvent resistance, and printing adhesion are improved.

As the melamine-based crosslinking agent, melamine, alkylated melamine, methylol melamine, alkoxylated methylmelamine and the like can be used.

In addition, as the isocyanate crosslinking agent, it is preferable to use a blocked isocyanate crosslinking agent which is stable in an aqueous solution. As specific examples of the blocked isocyanate-based crosslinking agent, an isocyanate-based crosslinking agent (for example, an isocyanate compound used in a pressure-sensitive adhesive layer described below) that can be used in preparing a general pressure-sensitive adhesive layer or antistatic layer (topcoat layer) , Thiophenols, amines, imides, oximes, lactams, active methylene compounds, mercaptans, imines, ureas, diaryl compounds, and sodium bisulfite.

Antistatic agents, colorants (pigments, dyes, etc.), flow control agents (thixotropic agents, thickeners, etc.), film forming aids, surfactants (defoamers, etc.) Preservatives, and the like. It is also possible to add a glycidyl compound, a polar solvent, a polyvalent aliphatic alcohol, a lactam compound and the like as the conductivity improver.

&Lt; Formation of antistatic layer >

The antistatic layer (top coat layer) is formed by laminating a liquid composition (a coating material for forming an antistatic layer, an antistatic agent composition) dissolved or dispersed in an appropriate solvent (water or the like) in an essential component such as the conductive polymer component, To the base material. For example, the coating material may be preferably applied to the first surface of the substrate, followed by drying, and optionally curing (heat treatment, ultraviolet ray treatment, etc.). The NV (nonvolatile matter) of the coating material may be, for example, 5 mass% or less (typically 0.05 to 5 mass%), and usually 1 mass% or less (typically 0.10 to 1 mass% . In the case of forming the antistatic layer having a small thickness, the NV of the coating material is preferably 0.05 to 0.50 mass% (for example, 0.10 to 0.40 mass%). By using such a low NV coating material, a more uniform antistatic layer can be formed.

As the solvent constituting the coating material for forming the antistatic layer, it is preferable that the antistatic layer can stably dissolve or disperse the components to be formed. Such a solvent may be an organic solvent, water, or a mixture thereof. Examples of the organic solvent include esters such as ethyl acetate; Ketones such as methyl ethyl ketone, acetone, and cyclohexanone; Cyclic ethers such as tetrahydrofuran (THF) and dioxane; aliphatic or alicyclic hydrocarbons such as n-hexane and cyclohexane; Aromatic hydrocarbons such as toluene and xylene; Aliphatic or alicyclic alcohols such as methanol, ethanol, n-propanol, isopropanol, and cyclohexanol; Glycol ethers such as alkylene glycol monoalkyl ethers (e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether) and dialkylene glycol monoalkyl ether; And the like can be used. In a preferred embodiment, the solvent of the coating material is water or a mixed solvent mainly composed of water (for example, a mixed solvent of water and ethanol).

In addition, in order to improve dispersion stability to a solvent, a basic organic compound capable of coordinating or bonding as an ion pair to an anion group of a polyanion may be included. Examples of the basic organic compound include a known amine compound, a hydrochloride salt of an amine compound, a cationic emulsifier, and a basic resin.

Specific examples of the basic organic compound include methyloctylamine, methylbenzylamine, N-methylaniline, dimethylamine, diethylamine, diethanolamine, N-methylethanolamine, di-n-propylamine, diisopropylamine , Methyl-isopropanolamine, dibutylamine, di-2-ethylhexylamine, aminoethylethanolamine, 3-amino-1-propanol, isopropylamine, monoethylamine, 2-ethylhexylamine, Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) Amines such as ethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane, monomethylamine, monoethylamine, stearylamine , Hydrochloric acid salts of primary amines such as hydrochloric acid, nitric acid, sulfuric acid, nitric acid, sulfuric acid, A salt of a tertiary amine such as trimethylamine, triethylamine or stearyldimethylamine, a quaternary ammonium salt such as stearyltrimethylammonium chloride, distearyldimethylammonium chloride or stearyldimethylbenzylammonium chloride, a monoethanolamine, Hydrochloride of ethanolamine such as diethanolamine and triethanolamine, and hydrochloride of polyethylenepolyamines such as ethylenediamine and diethylenetriamine.

Specific examples of the cationic emulsifier include alkylammonium salts, alkylamide betaines, alkyldimethylamine oxides, and the like.

Specific examples of the basic resin include a polyester-based, an acrylic-based, and a urethane-based polymer copolymer and have a weight average molecular weight (Mw) of 1,000 to 1,000,000. If the weight average molecular weight of the basic resin is less than 1000, sufficient steric hindrance may not be obtained and the dispersing effect may be lowered. On the other hand, if the weight average molecular weight is larger than 1, 000, the cohesive action may occur.

The amine value of the basic resin is preferably 5 to 200 mgKOH / g. If it is less than 5 mgKOH / g, the interaction of the polythiophenes with the doped polyanions tends to be insufficient, and a sufficient dispersing effect may not be obtained. On the other hand, if the amine value of the basic resin is more than 200 mgKOH / g, the steric hindrance layer may be less than the affinity for the polyanions doped in the polythiophene, resulting in insufficient dispersion effect.

Examples of the basic resin include Solsperse17000, Solsperse20000, Solsperse24000, Solsperse32000 (manufactured by Zeneca), Disperbyk-160, Disperbyk-161, Disperbyk-162, Disperbyk-163, Disperbyk-170, Disperbyk-2000, Disperbyk-2001 (Manufactured by EI du Pont de Nemours and Company), Ajisper PB711, Ajisper PB821, Ajisper PB822, Ajisper PB824 (manufactured by Ajinomoto KK), Epomin006, Epomin012, Epomin018 (manufactured by Nippon Catalysts Co., Ltd.), EFKA4046, EFKA4300, EFKA4330, EFKA4510 (Manufactured by Kusumoto Chemical Co., Ltd.), and the like, and they can be used alone or in combination. Particularly, Ajisper PB821, Ajisper PB822 and Ajisper PB824 are preferable in terms of dispersibility and conductivity in use.

The amount of the basic compound to be used is not limited, but it is preferably added in a range of 1 part by mass to 100,000 parts by mass, preferably 10 parts by mass to 1 million parts by mass, based on 100 parts by mass of the total of the polythiophenes and the polyanions Do.

&Lt; Characteristics of Antistatic Layer >

The thickness of the antistatic layer in the techniques disclosed herein is typically 3 to 500 nm, preferably 3 to 100 nm, and more preferably 3 to 60 nm. When the thickness of the antistatic layer is too small, it is difficult to uniformly form the antistatic layer (for example, the thickness of the antistatic layer varies in accordance with the location) It can be easily generated. On the other hand, if the thickness is excessively large, the characteristics (optical characteristics, dimensional stability, etc.) of the substrate may be affected.

In one preferred form of the surface protective film disclosed herein, the surface resistivity (Ω / □) measured on the surface of the antistatic layer is preferably less than 1.0 × 10 ¹¹ , more preferably less than 5.0 × 10 ¹⁰ and, still more preferably less than 1.0 × 10 ^10. The surface protective film exhibiting the surface resistivity within the above range can be suitably used as a surface protective film used in, for example, processing or transporting an article such as a liquid crystal cell, a semiconductor device, and the like, which dislikes static electricity. The surface resistivity can be calculated from the surface resistivity measured under an atmosphere of 23 캜 and 50% RH using a commercially available insulation resistance measuring apparatus.

It is preferable that the surface protective film disclosed herein has such a property that the back surface (the surface of the antistatic layer) can be easily printed by using a water-based ink or an oil-based ink (for example, by using an oil-based marking pen). Such a surface protective film may be provided on the surface protective film by displaying the identification number of the object to be protected on the surface protective film in the process of processing or transporting an adherend (for example, an optical component) Lt; / RTI &gt; Therefore, it is preferable that the surface protective film is excellent in printability. For example, it is preferable that the solvent has a high printing property with respect to the oil type ink which is a type including an ink as an alcohol system. It is also preferable that the printed ink is hard to be dropped by friction or electrodeposition (that is, excellent in print adhesion). It is preferable that the surface protective film disclosed herein also has a solvent resistance such that when the print is modified or removed, the print is wiped with alcohol (for example, ethyl alcohol), no noticeable change occurs in appearance.

The surface protective film disclosed herein can be also applied to a form including another layer in addition to the base material, the pressure-sensitive adhesive layer, and the antistatic layer. The arrangement of the "other layer" includes, for example, between the second surface (front surface) of the substrate and the pressure-sensitive adhesive layer. The layer disposed between the substrate front surface and the pressure sensitive adhesive layer may be, for example, an undercoat layer (anchor layer) for increasing the anchoring property of the pressure sensitive adhesive layer to the second surface, an antistatic layer, or the like. It may be a surface protective film having an antistatic layer disposed on the front surface of the substrate, an anchor layer disposed on the antistatic layer, and a pressure sensitive adhesive layer disposed thereon.

&Lt; Pressure sensitive adhesive composition &

The surface protective film of the present invention has the above-mentioned pressure sensitive adhesive layer, and the pressure sensitive adhesive layer is formed of a pressure sensitive adhesive composition. The pressure sensitive adhesive composition can be used without particular limitation as long as it has adhesiveness. Examples thereof include acrylic pressure sensitive adhesives, urethane pressure sensitive adhesives, , Natural rubber-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, etc. Among these, at least one kind selected from the group consisting of acrylic pressure-sensitive adhesives, urethane pressure-sensitive adhesives, and silicone pressure-sensitive adhesives is more preferable, and (meth) Based acrylic pressure-sensitive adhesive.

When the pressure-sensitive adhesive layer uses an acrylic pressure-sensitive adhesive, the (meth) acryl-based polymer constituting the acrylic pressure-sensitive adhesive may use a (meth) acrylic monomer having an alkyl group of 1 to 14 carbon atoms as a main monomer have. The (meth) acrylic monomers may be used alone or in combination of two or more. By using the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, it is easy to control the peeling force (adhesive force) on the adherend (subject to be protected) to be low, A surface protective film is obtained. The (meth) acryl-based polymer in the present invention refers to an acryl-based polymer and / or a methacryl-based polymer, and (meth) acrylate refers to acrylate and / or methacrylate.

Specific examples of the (meth) acrylic monomers having an alkyl group having 1 to 14 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, Acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (Meth) acrylate, n-decyl (meth) acrylate, n-octyl (meth) acrylate, -Tridecyl (meth) acrylate, and n-tetradecyl (meth) acrylate.

In particular, the surface protective film of the present invention may contain at least one of hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, (Meth) acrylate, n-decyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (Meth) acrylic monomers having an alkyl group having 6 to 14 carbon atoms such as tetradecyl (meth) acrylate are preferable. Particularly, by using a (meth) acrylic monomer having an alkyl group having 6 to 14 carbon atoms, it is easy to control the peeling force (adhesive force) to the adherend to be low, and the re-peeling property is excellent.

In particular, the (meth) acrylic polymer preferably contains 50 mass% or more of a (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms relative to 100 mass% of the entire monomer component constituting the (meth) acrylic polymer, more preferably 60 mass% %, More preferably 70 to 99 mass%, and most preferably 80 to 98 mass%. If it is less than 50% by mass, the wettability of the pressure-sensitive adhesive composition or the cohesive force of the pressure-sensitive adhesive layer may be deteriorated.

Further, in the pressure-sensitive adhesive composition of the present invention, it is preferable that the (meth) acryl-based polymer contains a hydroxyl group-containing (meth) acrylic monomer as a raw material monomer. The hydroxy group-containing (meth) acrylic monomer may be used alone or in combination of two or more.

By using the hydroxy group-containing (meth) acrylic monomer, it becomes easy to control the crosslinking of the pressure-sensitive adhesive composition, and the balance between the improvement of the wettability due to flow and the reduction of the peeling force (adhesive force) . In addition, unlike a carboxyl group or a sulfonate group which can generally act as a crosslinking site, the hydroxy group has an appropriate interaction with an ionic compound or an antioxidant, which is an antistatic component (antistatic agent) Can be used.

Examples of the hydroxyl group-containing (meth) acrylic monomers include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) (Meth) acrylate, hexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl Methyl (meth) acrylate, N-methylol (meth) acrylamide and the like. Particularly, the use of a hydroxy group-containing (meth) acryl-based monomer having at least 4 carbon atoms in the alkyl group makes it possible to facilitate delamination at high-speed peeling, which is preferable.

More preferably 1 to 22 parts by mass, still more preferably 25 to 30 parts by mass, still more preferably 5 to 30 parts by mass, per 100 parts by mass of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms Preferably 2 to 20 parts by mass, and most preferably 3 to 18 parts by mass. Within this range, it is preferable to control the balance between the wettability of the pressure-sensitive adhesive composition and the cohesive force of the resulting pressure-sensitive adhesive layer.

Further, as the other polymerizable monomer component, the glass transition temperature and the peelability of the (meth) acryl-based polymer are adjusted so that the Tg becomes 0 deg. C or lower (usually -100 deg. C or higher) Can be used within a range that does not impair the effects of the present invention.

Examples of other polymerizable monomers other than the (meth) acrylic monomers having an alkyl group having 1 to 14 carbon atoms and the hydroxy group-containing (meth) acrylic monomers used in the (meth) acryl-based polymer include monomers having a carboxyl group- .

Examples of the carboxyl group-containing (meth) acrylic monomers include (meth) acrylic acid, carboxyethyl (meth) acrylate and carboxypentyl (meth) acrylate.

The carboxyl group-containing (meth) acrylic monomer is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and 2 parts by mass or less, based on 100 parts by mass of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms And most preferably 0.01 part by mass or less and less than 0.1 part by mass. When an ionic compound or a polyether compound, which is an antistatic component (antistatic agent), is added in the presence of a large number of acid functional groups such as a carboxyl group having a large polarity action when it exceeds 5 parts by mass, an acid such as a carboxyl group The interaction of the functional groups interferes with the ion conduction and the conduction efficiency is lowered, and sufficient antistatic properties can not be obtained, which is not preferable.

Examples of other polymerizable monomers other than the (meth) acrylic monomers having an alkyl group having 1 to 14 carbon atoms, the hydroxyl group-containing (meth) acrylic monomers and the carboxyl group-containing (meth) acrylic monomers used in the (meth) , And is not particularly limited as far as the properties of the present invention are not impaired. For example, a cohesive force / heat resistance-enhancing component such as a cyano group-containing monomer, a vinyl ester monomer, an aromatic vinyl monomer, or the like, or an amide group-containing monomer, an imide group-containing monomer, an amino group-containing monomer, an epoxy group-containing monomer, N-acryloylmorpholine, It is possible to appropriately use a component having a functional group which acts as an improvement point of a peeling force (adhesive force) such as an ether monomer or as a point of crosslinking. Among them, it is preferable to use a cyano group-containing monomer, an amide group-containing monomer, an imide group-containing monomer, an amino group-containing monomer, and a nitrogen-containing monomer such as N-acryloylmorpholine. By using the nitrogen-containing monomer, a suitable peeling force (adhesive force) that does not cause floating or peeling can be ensured, and a surface protective film excellent in shear force can be obtained. These polymerizable monomers may be used alone or in combination of two or more.

Examples of the cyano group-containing monomer include acrylonitrile and methacrylonitrile.

Examples of the amide group-containing monomer include acrylamide, methacrylamide, diethylacrylamide, N-vinylpyrrolidone, N, N-dimethylacrylamide, N, N, N'-methylenebisacrylamide, N, N-dimethylaminopropylacrylamide, N, N-dimethylaminopropylmethacrylamide, diacetone acrylamide And the like.

Examples of the imide group-containing monomer include cyclohexylmaleimide, isopropylmaleimide, N-cyclohexylmaleimide and itaconimide.

Examples of the amino group-containing monomer include aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl laurate, and the like.

Examples of the aromatic vinyl monomer include styrene, chlorostyrene, chloromethylstyrene,? -Methylstyrene, and other substituted styrenes.

Examples of the epoxy group-containing monomer include glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, and allyl glycidyl ether.

Examples of the vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether and the like.

In the present invention, other polymerizable monomers other than the (meth) acrylic monomers having an alkyl group of 1 to 14 carbon atoms, the hydroxy group-containing (meth) acrylic monomers and the carboxyl group-containing (meth) Is preferably 0 to 40 parts by mass, more preferably 0 to 30 parts by mass with respect to 100 parts by mass of the (meth) acryl-based monomer having When the above-mentioned other polymerizable monomer is used within the above-mentioned range, when an ionic compound or a polyether compound which is an antistatic component is used, good interaction and good re-peeling property can be appropriately controlled.

The (meth) acryl-based polymer further contains an alkylene oxide group-containing reactive monomer as a monomer component.

The average addition mole number of oxyalkylene units in the alkylene oxide group-containing reactive monomer is preferably 1 to 40, more preferably 3 to 40, and more preferably 3 to 40, in view of compatibility with the ionic compound or polyether compound, More preferably from 4 to 35, and particularly preferably from 5 to 30. When the average added mole number is 1 or more, there is a tendency that the effect of reducing the stain on the adherend (subject to be protected) is efficiently obtained. When the average addition molar number is more than 40, the interaction with the ionic compound or the polyether compound is large, and the viscosity of the pressure-sensitive adhesive composition tends to increase and the coating tends to become difficult, which is not preferable. The terminal of the oxyalkylene chain may be substituted with a hydroxyl group or other functional group.

The alkylene oxide group-containing reactive monomer may be used singly or in admixture of two or more, but it is preferably contained in a total amount of 20 mass% or less in the total monomer component of the (meth) acrylic polymer, more preferably 10 mass% Or less, more preferably 5 mass% or less, further preferably 4 mass% or less, particularly preferably 3 mass% or less, further preferably 1 mass% or less. When the content of the alkylene oxide group-containing reactive monomer exceeds 20 mass%, the interaction with the ionic compound or the polyether compound becomes large, which hinders ion conduction and lowers the antistatic property.

Examples of the oxyalkylene unit of the alkylene oxide group-containing reactive monomer include those having an alkylene group having 1 to 6 carbon atoms, and examples thereof include an oxymethylene group, an oxyethylene group, an oxypropylene group, and an oxybutylene group. . The hydrocarbon group of the oxyalkylene chain may be straight-chain or branched.

Further, it is more preferable that the alkylene oxide group-containing reactive monomer is a reactive monomer having an ethylene oxide group. The use of the (meth) acryl-based polymer having a reactive monomer having an ethylene oxide group as the base polymer improves the compatibility of the base polymer with the ionic compound or the polyether compound as the antistatic component, And a pressure-sensitive adhesive composition of low stain resistance is obtained.

Examples of the alkylene oxide group-containing reactive monomer include alkylene oxide adducts of (meth) acrylic acid and reactive surfactants having reactive substituents such as acryloyl groups, methacryloyl groups and allyl groups in the molecule, and the like have.

Specific examples of the (meth) acrylic acid alkylene oxide adduct may include polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, polyethylene glycol-polypropylene glycol (meth) acrylate, polyethylene glycol- (Meth) acrylate, butoxypolyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, butoxypolyethylene glycol (Meth) acrylate, octoxypolyethylene glycol (meth) acrylate, lauroxypolyethylene glycol (meth) acrylate, stearoxypolyethylene glycol (meth) acrylate, phenoxypolyethylene glycol ) Acrylate, octoxypolyethylene glycol-polypropylene glycol (Meth) acrylate, and the like.

Specific examples of the reactive surfactant include anionic type reactive surfactants having a (meth) acryloyl group or an allyl group, nonionic reactive surfactants, and cationic reactive surfactants.

The weight average molecular weight (Mw) of the (meth) acryl-based polymer is preferably 100,000 to 5,000,000, more preferably 200,000 to 4,000,000, and still more preferably 300,000 to 3,000,000. When the weight average molecular weight is less than 100,000, the cohesive force of the pressure-sensitive adhesive layer becomes small, and tacky residues tends to be generated. On the other hand, when the weight average molecular weight exceeds 500,000, the fluidity of the polymer is lowered and the wettability to an adherend (for example, a polarizing plate) becomes insufficient, so that the adhesion between the adherend and the pressure- Tends to cause blistering. The weight average molecular weight refers to a value obtained by measurement by GPC (gel permeation chromatography).

The glass transition temperature (Tg) of the (meth) acryl-based polymer is preferably 0 ° C or lower, more preferably -10 ° C or lower (usually -100 ° C or higher). When the glass transition temperature is higher than 0 占 폚, the polymer tends not to flow, for example, the wettability to the polarizing plate becomes insufficient, and tends to cause blistering occurring between the polarizing plate and the pressure-sensitive adhesive layer of the surface protective film. Especially when the glass transition temperature is lower than -61 캜, it is easy to obtain a pressure-sensitive adhesive layer excellent in wettability and light fastness to a polarizing plate. The glass transition temperature of the (meth) acryl-based polymer can be adjusted within the above-mentioned range by suitably changing the monomer components or the composition ratio to be used.

The polymerization method of the (meth) acryl-based polymer is not particularly limited, and polymerization can be carried out by a known method such as solution polymerization, emulsion polymerization, bulk polymerization and suspension polymerization. In particular, from the viewpoint of workability, ), The solution polymerization is a more preferable form. The obtained polymer may be any of a random copolymer, a block copolymer, a mutual copolymer and a graft copolymer.

When a urethane-based pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, any appropriate urethane-based pressure-sensitive adhesive can be employed. Examples of such a urethane pressure-sensitive adhesive include those comprising a urethane resin (urethane-based polymer) obtained by reacting a polyol with a polyisocyanate compound. Examples of polyols include polyether polyols, polyester polyols, polycarbonate polyols, polycaprolactone polyols, and the like. Examples of the polyisocyanate compound include diphenylmethane diisocyanate, tolylene diisocyanate, and hexamethylene diisocyanate.

When a silicone-based pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, any suitable silicone-based pressure-sensitive adhesive can be employed. As such a silicone-based pressure-sensitive adhesive, those obtained by mixing or agglomerating a silicone resin (a silicone-based polymer or a silicone component) can be preferably employed.

Examples of the silicone pressure-sensitive adhesive include an addition cure type silicone pressure-sensitive adhesive and a peroxide curing type silicone pressure-sensitive adhesive. Among these silicone adhesives, an addition reaction curing type silicone adhesive is preferred because no peroxide (benzoyl peroxide, etc.) is used and no decomposition products are generated.

As the curing reaction of the addition reaction curing type silicone pressure-sensitive adhesive, for example, in the case of obtaining a polyalkyl silicone pressure-sensitive adhesive, a method of generally curing the polyalkyl hydrogen siloxane composition with a platinum catalyst can be mentioned.

&Lt; Antistatic component in pressure-sensitive adhesive layer >

In the surface protective film of the present invention, the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer preferably contains an antistatic component, and more preferably contains an ionic compound as the antistatic component. Examples of the ionic compound include an alkali metal salt and / or an ionic liquid. By containing these ionic compounds, excellent antistatic properties can be imparted. In addition, the pressure-sensitive adhesive layer (using the antistatic component) formed by crosslinking the pressure-sensitive adhesive composition containing the antistatic component as described above is capable of preventing electrification of an adherend (for example, a polarizing plate) Thus, the surface protective film is reduced in contamination to the adherend. Therefore, it becomes very useful as an antistatic surface protective film in a technical field related to optical and electronic parts in which electrification and contamination are particularly serious problems.

Since the alkali metal salt has high ion dissociation property, it is preferable from the viewpoint of exhibiting an excellent antistatic function even in a small amount. Examples of the alkali metal salt include a cation selected from the group consisting of Li ⁺ , Na ⁺ , K ⁺ and a cation selected from Cl ^- , Br ^- , I ^- , AlCl ₄ ^- , Al ₂ Cl ₇ ^- , BF ₄ ^- , PF ₆ ^- , SCN ^-, ClO ₄ ^{-, _{NO 3 -, CH 3 COO -}} , C 9 H 19 COO -, CF 3 COO -, C 3 F 7 COO -, CH 3 SO 3 -, CF 3 SO 3 -, C 4 F 9 SO 3 -, C 2 _{^{H 5 OSO 3 -, C 6}} H 13 OSO 3 -, C 8 H 17 OSO 3 -, (CF 3 SO 2) 2 N -, (C 2 F 5 SO 2) 2 N -, (C 3 F 7 SO ₂ ) N ₂ ^- , (C ₄ F ₉ SO ₂ ) ₂ N ^- , (CF ₃ SO ₂ ) ₃ C ^- , AsF ₆ ^- , SbF ₆ ^- , NbF ₆ ^- , TaF ₆ ^- , HF ₂ ^{- _{) 2 N -, (CF 3}} SO 2) (CF 3 CO) N -, (CH 3) 2 PO 4 -, (C 2 H 5) 2 PO 4 -, CH 3 (OC 2 H 4) 2 OSO 3 _{^{-, C 6 H 4 (CH}} 3) SO 3 -, (C 2 F 5) 3 PF 3 -, CH 3 CH (OH) COO -, and (FSO _{2) 2} N ^- preferably a metal salt consisting of an anion consisting of Lt; / RTI &gt; Li (CF ₃ SO ₂ ) ₂ N, Li (C ₂ F ₅ SO ₂ ) ₂ N, Li (FSO), and the like are more preferably used as LiBF ₄ , LiBF ₄ , LiPF ₆ , LiSCN, LiClO ₄ , LiCF ₃ SO ₃ , Li _{2) 2 N, Li (CF} 3 SO 2) 3 lithium salt, such as C, and more preferably from _{LiCF 3 SO 3, Li (CF} 3 SO 2) 2 N, Li (C 2 F 5 SO 2) 2 N, Li (C ₃ F ₇ SO ₂ ) ₂ N, Li (C ₄ F ₉ SO ₂ ) ₂ N, Li (FSO ₂ ) ₂ N and Li (CF ₃ SO ₂ ) ₃ C are used. These alkali metal salts may be used alone or in combination of two or more.

Further, by using the ionic liquid as an antistatic component (antistatic agent), a pressure-sensitive adhesive layer having a high antistatic effect can be obtained without deteriorating the adhesive property. The reason why excellent antistatic properties can be obtained by using an ionic liquid is not clear. However, since ionic liquids have a low melting point (melting point of 100 DEG C or lower) as compared with general ionic compounds, Function is obtained. In particular, when antistatic treatment to the adherend is desired, it can be considered that the ionic liquid is transferred to the adherend in a very small amount, thereby achieving excellent peeling electrification prevention in the adherend. Particularly, an ionic liquid having a melting point at room temperature (25 캜) or lower can be more efficiently transferred to an adherend, and thus excellent antistatic properties can be obtained.

Further, since the ionic liquid is in a liquid phase at 100 DEG C or lower, addition, dispersion or dissolution of the ionic liquid into the pressure-sensitive adhesive can be easily performed compared with a solid salt. Further, since the ionic liquid has no vapor pressure (nonvolatile), it does not disappear over time and has characteristics in which antistatic characteristics are continuously obtained. An ionic liquid refers to a molten salt (ionic compound) which exhibits a liquid phase at a melting point of 100 ° C or lower.

As the ionic liquid, those comprising an organic cation component and an anion component represented by the following general formulas (A) to (E) are preferably used. An ionic liquid having these cations can further provide an excellent antistatic function.

[Chemical Formula 1]

In the formula (A), R _a represents a hydrocarbon group having 4 to 20 carbon atoms, a part of the hydrocarbon group may be a functional group substituted with a hetero atom, R _b and R _c may be the same or different, Or a hydrocarbon group in which a part of the hydrocarbon group is substituted with a hetero atom. However, when the nitrogen atom contains a double bond, there is no R _c .

The formula (B) of the R _d is C2 to represent 20 hydrocarbon group of, a portion of the hydrocarbon group may be a hetero atom substituted functional group, R _e, R _f and R _g are the same or different and hydrogen or A hydrocarbon group having 1 to 16 carbon atoms and a hydrocarbon group in which a part of the hydrocarbon group is substituted with a hetero atom.

R _h in the formula (C) represents a hydrocarbon group having 2 to 20 carbon atoms, a part of the hydrocarbon group may be a functional group substituted with a hetero atom, R _i , R _j and R _k are the same or different, A hydrocarbon group having 1 to 16 carbon atoms and a hydrocarbon group in which a part of the hydrocarbon group is substituted with a hetero atom.

In formula (D), Z represents a nitrogen, sulfur or phosphorus atom, and R ₁ , R _m , R _n and R _o are the same or different and represent a hydrocarbon group of 1 to 20 carbon atoms, May be a functional group substituted with a hetero atom. Provided that when Z is a sulfur atom, R _o is absent.

In the formula (E), R _P represents a hydrocarbon group having 1 to 18 carbon atoms, and the hydrocarbon group may be a functional group in which a part of the hydrocarbon group is substituted with a hetero atom.

Examples of the cation represented by the formula (A) include a pyridinium cation, a piperidinium cation, a pyrrolidinium cation, a cation having a pyrrolene skeleton, a cation having a pyrrole skeleton, and a morpholinium cation.

Specific examples include, for example, a cation such as 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1 -butyl-3-methylpyridinium cation, , 1-hexyl-3-methylpyridinium cation, 1-butyl-3,4-dimethylpyridinium cation, 1,1-dimethylpyrrolidinium cation, Methyl-1-pentylpyrrolidinium cation, 1-methyl-1-hexylpyrrolidinium cation, 1-methyl-1-butylpyrrolidinium cation, Ethyl-1-propylpyrrolidinium cation, 1-ethyl-1-butylpyrrolidinium cation, 1-ethyl-1-pentylpyrrolidinium cation, 1-ethyl- Ethyl-1-heptylpyrrolidinium cation, 1,1-dipropylpyrrolidinium cation, 1-propyl-1-butylpyrrolidinium cation, 1,1-dibutylpyrrolidinium cation, , Pyrrolidinium-2-one cations, 1-methylpiperidinium cation, 1-methylpiperidinium cation, 1-methyl-1-propylpiperidinium cation, 1- Methyl-1-butylpiperidinium cation, 1-methyl-1-pentylpiperidinium cation, 1-methyl-1-hexylpiperidinium cation, Ethyl-1-butylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation, Propyl-1-butylpiperidinium cation, a 1,1-dibutylpiperidinium cation, a 2-methyl-1-pyrroline cation, Ethyl-2-phenylindole cation, a 1,2-dimethyl indole cation, a 1-ethylcarbazole cation and an N-ethyl-N-methylmorpholinium cation.

Examples of the cation represented by the formula (B) include an imidazolium cation, a tetrahydropyrimidinium cation, and a dihydropyrimidinium cation.

Specific examples include, for example, a cation selected from the group consisting of 1,3-dimethylimidazolium cation, 1,3-diethylimidazolium cation, 1-ethyl-3-methylimidazolium cation, 3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, Dimethylimidazolium cation, 1-ethyl-2,3-dimethylimidazolium cation, 1-butyl-2,3-dimethylimidazolium cation, Dimethylimidazolium cation, 1-hexyl-2,3-dimethylimidazolium cation, 1- (2-methoxyethyl) -3-methylimidazolium cation, 6-tetrahydropyrimidinium cation, 1,2,3-trimethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4,5,6 - tetrahydropyrimidinium cation, 1,2,3,5-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,3- Dimethyl-1,4-dihydropyrimidinium cation, 1,3-dimethyl-1,6-dihydropyrimidinium cation, 1,2,3-trimethyl-1,4-dihydropyrimidinium cation, , 2,3-trimethyl-1,6-dihydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4-dihydropyrimidinium cation, 1,2,3,4-tetramethyl -1,6-dihydropyrimidinium cation, and the like.

Examples of the cation represented by the formula (C) include a pyrazolium cation and a pyrazolinium cation.

Specific examples include, for example, 1-methylpyrazolium cation, 3-methylpyrazolium cation, 1-ethyl-2-methylpyrazolinium cation, 1-ethyl-2,3,5-trimethylpyrazolium cation, 1- Propyl-2,3,5-trimethylpyrazolium cation, 1-butyl-2,3,5-trimethylpyrazolium cation, 1-ethyl-2,3,5-trimethylpyrazolinium cation, 3,5-trimethylpyrazolinium cation, 1-butyl-2,3,5-trimethylpyrazolinium cation, and the like.

Examples of the cation represented by the formula (D) include tetraalkylammonium cations, trialkylsulfonium cations, tetraalkylphosphonium cations, and those in which a part of the alkyl group is substituted with an alkenyl group, an alkoxy group, or an epoxy group .

Specific examples thereof include, for example, tetramethylammonium cations, tetraethylammonium cations, tetrabutylammonium cations, tetrapentylammonium cations, tetrahexylammonium cations, tetraheptylammonium cations, triethylmethylammonium cations, tributylethylammonium cations, trimethyl (2-methoxyethyl) ammonium cation, a glycidyltrimethylammonium cation, a trimethylsulfonium cation, a triethylsulfonium cation, a tributylsulfonium cation , Trihexylsulfonium cation, diethylsulfonium cation, dibutylethylsulfonium cation, dimethyldesilsulfonium cation, tetramethylphosphonium cation, tetraethylphosphonium cation, tetrabutylphosphonium cation, tetrahexylphosphonium cation , Tetraoctylphosphonium cation, triethylmethylphosphonium cation, tributylethylphosphonium cation, And the like (2-methoxyethyl) phosphonium cation-Lee methyl decyl phosphonium cation, diallyldimethylammonium cation, tributylammonium. Among them, triethylmethylammonium cation, tributylethylammonium cation, trimethyldecylammonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, dimethyldesylsulfonium cation, triethylmethylphosphonium cation, tributylethylphosphine A trialkylsulfonium cation, a tetraalkylphosphonium cation, or an N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium N, N-dimethyl-N-ethyl-N-butylammonium cation, N, N-dimethyl-N-ethyl-N-propylammonium cation, Dimethyl-N-ethyl-N-heptylammonium cation, N, N-dimethyl-N-ethyl-N-pentylammonium cation, N-ethyl-N-nonyl ammonium cation, N, N-dimethyl-N, Dimethyl-N-propyl-N-pentylammonium cation, N, N-dimethyl-N-propyl-N-hexylammonium cation, , N, N-dimethyl-N-propyl-N-heptylammonium cation, N, N-dimethyl- N, N-dimethyl-N, N-diethylamino ammonium cation, N, N-dimethyl-N-pentyl-N-hexylammonium cation, Ammonium cation, an N, N-diethyl-N-methyl-N-pentylammonium cation, an N, N-diethyl- N-methyl-N-methyl-N-ethylammonium cation, N, N-dipropyl-N-methyl- N-dipropyl-N-butyl-N-hexylammonium cation, N, N-dipropyl-N, N-di N, N-dibutyl-N-methyl-N-hexylammonium cation, trioctylmethylammonium cation, N-methyl-N- Ethyl-N-propyl-N-pentylammonium cations are preferably used.

Examples of the cation represented by the formula (E) include a sulfonium cation and the like. Specific examples of R _P in the formula (E) include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, a tridecyl group, a tetradecyl group, And the like.

On the other hand, the anion component is not particularly limited as long as it is an ionic liquid, and examples thereof include Cl ^- , Br ^- , I ^- , AlCl ₄ ^- , Al ₂ Cl ₇ ^- , BF ₄ ^- , PF ₆ ^{- _{ClO 4 -, NO 3 -,}} CH 3 COO -, CF 3 COO -, CH 3 SO 3 -, CF 3 SO 3 -, C 4 F 9 SO 3 -, (CF 3 SO 2) 2 N -, (C _{2 F 5 SO 2) 2 N} -, (C 3 F 7 SO 2) 2 N -, (C 4 F 9 SO 2) 2 N -, (CF 3 SO 2) 3 C -, AsF 6 -, SbF 6 _{^{-, NbF 6 -, TaF 6}} -, HF 2 -, (CN) 2 N -, C 4 F 9 SO 3 -, (C 2 F 5 SO 2) 2 N -, C 3 F 7 COO -, (CF _{3 SO 2) (CF 3 CO} ) N -, C 9 H 19 COO -, (CH 3) 2 PO 4 -, (C 2 H 5) 2 PO 4 -, C 2 H 5 OSO 3 -, C 6 H _{^{13 OSO 3 -, C 8 H}} 17 OSO 3 -, CH 3 (OC 2 H 4) 2 OSO 3 -, C 6 H 4 (CH 3) SO 3 -, (C 2 F 5) 3 PF 3 -, CH ₃ CH (OH) COO ^- , and (FSO ₂ ) ₂ N ^- are used.

As the anion component, an anion represented by the following formula (F) may also be used.

(2)

As an anionic component, an anionic component containing a fluorine atom is particularly preferably used because an ionic liquid having a low melting point is obtained.

As specific examples of the ionic liquid used in the present invention, one selected from a combination of the cationic component and the anionic component is appropriately selected and used. For example, 1-butylpyridinium tetrafluoroborate, 1-butylpyridinium hexafluorophosphate, 1 Butyl-3-methylpyridinium tetrafluoroborate, 1-butyl-3-methylpyridinium trifluoromethanesulfonate, 1-butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) 1-butyl-3-methylpyridinium bis (pentafluoroethanesulfonyl) imide, 1-hexylpyridinium tetrafluoroborate, 1,1-dimethylpyrrolidinium bis (trifluoromethanesulfonyl) imide Methyl-1-propylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-ethylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-butylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-pentylphenyl Methyl-1-hexylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-heptylpyrrolidinium bis (trifluoromethanesulfonyl) imide, Ethyl-1-propylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-butylpyrrolidinium bis (trifluoromethanesulfonyl) imide, Ethyl-1-pentylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-hexylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-heptylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1,1-dipropylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-propyl-1-butylpyrrolidinium bis (Trifluoromethanesulfonyl) imide, 1,1-dibutylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-propylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-Pentylviper (Trifluoromethanesulfonyl) imide, 1,1-dimethylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-ethylpiperidinium bis (trifluoromethanesulfonyl) imide, Methyl-1-propylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, 1 Methyl-1-pentylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-hexylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl- Ethyl-1-propylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, Ethyl-1-pentylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-hexylpiperidinium bis (trifluoromethanesulfonyl) imide, Imide, 1-ethyl-1-heptyl Propyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dipropylpiperidinium bis (trifluoromethanesulfonyl) imide, (Pentafluoroethanesulfonyl) imide, 1,1-dibutylpiperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dimethylpyrrolidinium bis (pentafluoroethanesulfonyl) Methyl-1-ethylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-propylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, Methyl-1-pentylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-hexylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, Methyl-1-heptylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-propylpyrrolidinium bis (pentafluoroethanesulfonyl) imide Di-1-ethyl-1 -Butylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-pentylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-hexylpyrrolidinium bis (Pentafluoroethanesulfonyl) imide, 1-ethyl-1-heptylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dipropylpyrrolidinium bis (pentafluoroethanesulfonyl) Imide, 1-propyl-1-butylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dibutylpyrrolidinium bis (pentafluoroethanesulfonyl) (Pentafluoroethanesulfonyl) imide, 1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dimethylpiperidinium bis (pentafluoroethanesulfonyl) Imide, 1-methyl-1-ethylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-propylpiperidinium bis (pentafluoroethanesulfonyl) -1-butylpyr Methyl-1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-hexylpiperidinium bis (pentafluoroethanesulfonyl) imide, Methyl-1-heptylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-propylpiperidinium bis (pentafluoroethanesulfonyl) imide, Ethyl-1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-butylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-hexylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-heptylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dipropylpiperidinium bis (Pentafluoroethanesulfonyl) imide, 1-propyl-1-butylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dibutylpiperidinium bis (pentafluoroethanesulfonyl) ) Imide, 2-methyl-1- Ethyl indole tetrafluoroborate, 1-ethyl indole tetrafluoroborate, 1-ethylcarbazole tetrafluoroborate, 1-ethyl-3-methylimidazole Ethyl-3-methylimidazolium trifluoroacetate, 1-ethyl-3-methylimidazolium heptafluorobutyrate, 1- Ethyl-3-methylimidazolium trifluoromethanesulfonate, 1-ethyl-3-methylimidazolium perfluorobutanesulfonate, 1-ethyl-3-methylimidazolium dicyanamide, 1-ethyl- 3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-ethyl-3-methylimidazolium bis (pentafluoroethanesulfonyl) imide, Tris (trifluoromethanesulfonyl) methide, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl- Butyl-3-methylimidazolium trifluoroacetate, 1-butyl-3-methylimidazolium heptafluorobutyrate, 1-butyl-3-methylimidazolium trifluoro Butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-hexyl-3-methyl Imidazolium bromide, 1-hexyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium hexafluorophosphate, 1- 3-methylimidazolium trifluoromethanesulfonate, 1-octyl-3-methylimidazolium tetrafluoroborate, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-hexyl- 3-dimethylimidazolium tetrafluoroborate, 1,2-dimethyl-3-propylimidazolium bis (trifluoromethanesulfonyl) 1-methylpyrazolium tetrafluoroborate, 2-methylpyrazolium tetrafluoroborate, 1-ethyl-2,3,5-trimethylpyrazoliumbis (trifluoromethanesulfonyl) imide, (Trifluoromethanesulfonyl) imide, 1-butyl-2,3,5-trimethylpyrazoliumbis (trifluoromethanesulfonyl) imide, 1-ethyl Trimethylpyrazoliumbis (pentafluoroethanesulfonyl) imide, 1-propyl-2,3,5-trimethylpyrazoliumbis (pentafluoroethanesulfonyl) imide, -2,3,5-trimethylpyrazoliumbis (pentafluoroethanesulfonyl) imide, 1-ethyl-2,3,5-trimethylpyrazoliumbis (trifluoromethanesulfonyl) trifluoroacetamide, 1-propyl-2,3,5-trimethylpyrazoliumbis (trifluoromethanesulfonyl) trifluoroacetamide, 1-butyl-2,3,5-trimethylpyrazoliumbis (trifluoromethanesulfonyl) triple Ethyl-2,3,5-trimethylpyrazolinium bis (trifluoromethanesulfonyl) imide, 1-propyl-2,3,5-trimethylpyrazolinium bis (trifluoromethane) Butyl-2,3,5-trimethylpyrazolinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-2,3,5-trimethylpyrazolinium bis (pentafluoro Propyl-2,3,5-trimethylpyrazolinium bis (pentafluoroethanesulfonyl) imide, 1-butyl-2,3,5-trimethylpyrazolinium bis ( Ethyl-2,3,5-trimethylpyrazolinium bis (trifluoromethanesulfonyl) trifluoroacetamide, 1-propyl-2,3,5-trimethyl (Trifluoromethanesulfonyl) trifluoroacetamide, 1-butyl-2,3,5-trimethylpyrazolinium bis (trifluoromethanesulfonyl) trifluoroacetamide, tetrapentylammonium Triple (Trifluoromethanesulfonyl) imide, tetrahexylammonium trifluoromethanesulfonate, tetrahexylammonium bis (trifluoromethanesulfonyl) imide, tetraheptylammonium trifluoroacetate, tetrahexylammonium trifluoroacetate, Tetrahexylammonium bis (trifluoromethanesulfonyl) imide, diallyldimethylammonium tetrafluoroborate, diallyldimethylammonium trifluoromethanesulfonate, diallyldimethylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium tetrafluoroborate, N, N-diethyl- N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium trifluoromethanesulfonate, N, Fluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N- (2- (Pentafluoroethanesulfonyl) imide, glycidyltrimethylammonium trifluoromethanesulfonate, glycidyltrimethylammonium bis (trifluoromethanesulfonyl) imide, glycidyltrimethylammonium bis (Pentafluoroethanesulfonyl) imide, tetraoctylphosphonium trifluoromethanesulfonate, tetraoctylphosphonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N- N-dimethyl-N-ethyl-N-butylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl- N, N-dimethyl-N-ethyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl- N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-nonylammonium bis (trifluoromethanesulfonyl) (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-butylammonium bis (trifluoromethanesulfonyl) imide, (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-hexylammonium bis (trifluoromethylsulfonyl) imide, N-dimethyl-N-butyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl- N-dimethyl-N-butyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-pentyl-N-hexylammonium bis (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N, N-dihexylammonium bis (trifluoromethanesulfonyl) imide, trimethylheptylammonium bis (trifluoromethanesulfonyl) imide , N, N-diethyl-N-methyl-N-propylammonium bis (trifluoromethane N, N-diethyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, triethylpropylammonium bis (trifluoromethanesulfonyl) imide, Imide, triethylpentylammonium bis (trifluoromethanesulfonyl) imide, triethylheptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N-methyl- N, N-dipropyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl- (Trifluoromethanesulfonyl) imide, N, N-dipropyl-N, N-dihexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dibutyl-N - methyl-N-pentylammonium bis (trifluoromethanesulfonyl) N, N-dibutyl-N-methyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, trioctylmethylammonium bis (trifluoromethanesulfonyl) Butylpyridinium (trifluoromethanesulfonyl) trifluoroacetamide, 1-butyl-3-methylpyridinium (trifluoromethanesulfonyl) (Trifluoromethanesulfonyl) trifluoroacetamide, 1-ethyl-3-methylimidazolium (trifluoromethanesulfonyl) trifluoroacetamide, N-ethyl-N-methylmorpholinium thio Cyanate, 4-ethyl-4-methylmorpholinium methyl carbonate, and the like.

The ionic liquid may be used alone, or two or more kinds may be mixed and used.

The content (total amount) of the antistatic component is preferably 1 part by mass or less, more preferably 0.001 to 0.9 part by mass, still more preferably 0.005 to 0.8 part by mass, further preferably 0.005 to 0.8 part by mass based on 100 parts by mass of the (meth) acryl- Most preferably 0.01 to 0.7 parts by mass. Within the above range, it is preferable since it is easy to combine antistatic property and low staining property.

&Lt; Polyether compound in pressure-sensitive adhesive layer >

In the surface protective film of the present invention, the pressure-sensitive adhesive composition preferably contains a polyether compound (polyether component), more preferably an organopolysiloxane having an oxyalkylene chain, More preferably, it contains an organopolysiloxane. It is presumed that the use of the above organopolysiloxane lowers the surface free energy of the surface of the pressure-sensitive adhesive and realizes light-releasing.

The organopolysiloxane is preferably an organopolysiloxane having a known polyoxyalkylene backbone, but is preferably represented by the following formula.

(3)

(Wherein R ₁ and / or R ₂ has an oxyalkylene chain having 1 to 6 carbon atoms, the alkylene group in the oxyalkylene chain may be straight-chain or branched, and the terminal of the oxyalkylene chain may be an alkoxy group or a hydroxy group Either R ₁ or R ₂ may be a hydroxy group, or may be an alkyl group or an alkoxy group, and the alkyl group or alkoxy group may be a functional group substituted with a hetero atom. )

The organopolysiloxane is one having a main chain containing a siloxane-containing site (siloxane moiety) and an oxyalkylene chain bonded to the end of the main chain. By using the organosiloxane having an oxyalkylene chain, a balance of compatibility with the (meth) acryl-based polymer, the antistatic component, and the like can be balanced, thereby realizing light exfoliation.

As the organopolysiloxane in the present invention, for example, the following constitution can be used. Specifically, in the formula, R ₁ and / or R ₂ has an oxyalkylene chain containing a hydrocarbon group having 1 to 6 carbon atoms, and as the oxyalkylene chain, an oxymethylene group, oxyethylene group, oxypropylene group, oxybutylene group Among them, an oxyethylene group and an oxypropylene group are preferable. When R ₁ and R ₂ together have an oxyalkylene chain, they may be the same or different.

[Chemical Formula 4]

The hydrocarbon group of the oxyalkylene chain may be straight-chain or branched.

The terminal of the oxyalkylene chain may be an alkoxy group or a hydroxy group, and more preferably an alkoxy group. In the case of adhering the separator to the surface of the pressure-sensitive adhesive layer for the purpose of protecting the pressure-sensitive adhesive surface, an interaction with the separator occurs in the organopolysiloxane having a hydroxyl group at the end, so that the sticking (peeling) force when the separator is peeled from the surface of the pressure- May rise.

Also, n is an integer of 1 to 300, preferably 10 to 200, and more preferably 20 to 150. When n is within the above range, the compatibility with the base polymer is balanced and a preferable form is obtained. The molecule may also have a reactive substituent such as a (meth) acryloyl group, an allyl group, or a hydroxyl group. These organopolysiloxanes may be used alone or in combination of two or more.

Specific examples of the organopolysiloxane having an oxyalkylene chain include commercially available products such as X-22-4952, X-22-4272, X-22-6266, KF-6004 and KF- BY16-201, SF8427 (manufactured by Dow Corning Toray Co., Ltd.) and IM22 (manufactured by Asahi Chemical Co., Ltd.). These compounds may be used alone or in combination of two or more.

In addition to the organosiloxane having an oxyalkylene chain in the main chain (bonding), it is also possible to use an organosiloxane having an oxyalkylene chain in the side chain (to be bonded) and an organosiloxane having an oxyalkyl chain in the side chain It is more preferable to use a siloxane. The organopolysiloxane is preferably an organopolysiloxane having a known polyoxyalkylene side chain, but is preferably represented by the following formula.

[Chemical Formula 5]

(Wherein, R ₁ is a monovalent organic group, R _2, R ₃ and R ₄ is an alkylene group, R ₅ is hydrogen or an organic group, m and n is an integer from 0 to 1000, except that, m, n are 0 at the same time A and b are integers between 0 and 100, provided that a and b are not 0 at the same time.

As the organopolysiloxane in the present invention, for example, the following constitution can be used. Specifically, in the formula, R ₁ is a monovalent organic group exemplified by an alkyl group such as a methyl group, an ethyl group or a propyl group, an aryl group such as a phenyl group or a trityl group or an aralkyl group such as a benzyl group or a phenethyl group, And may have a substituent. R ₂ , R ₃ and R ₄ may be alkylene groups having 1 to 8 carbon atoms such as a methylene group, an ethylene group and a propylene group. Here, R ₃ and R ₄ are different alkylene groups, and R ₂ may be the same as or different from R ₃ or R ₄ . R ₃ and R ₄ are preferably an ethylene group or a propylene group in order to increase the concentration of an antistatic component (for example, an ionic compound or the like) capable of dissolving in the polyoxyalkylene side chain. R ₅ may be a monovalent organic group exemplified by an alkyl group such as a methyl group, an ethyl group or a propyl group or an acyl group such as an acetyl group or a propionyl group and may have a substituent such as a hydroxy group. These compounds may be used alone or in combination of two or more. In addition, the molecule may have a reactive substituent such as a (meth) acryloyl group, an allyl group, or a hydroxyl group. Among these organosiloxanes having a polyoxyalkylene side chain, organosiloxane having a polyoxyalkylene side chain having a hydroxyl group terminal is preferable because it is presumed that the compatibility of the compatibilizing agent tends to be easily balanced.

[Chemical Formula 6]

Specific examples of the organosiloxane include trade names KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF- KF-6012, KF-6017, X-22-2516 (all manufactured by Shin-Etsu Chemical Co., Ltd.), KF-643, KF-6022, X-22-6191, X-22-4515, KF-6011, KF- , SF8428, FZ-2162, SH3749, FZ-77, L-7001, FZ-2104, FZ-2110, L-7002, FZ-2122, FZ-2164, FZ-2203, FZ-7001, SH8400, , SF8422 (manufactured by Toray / Dow Corning), TSF-4440, TSF-4441, TSF-4445, TSF-4450, TSF-4446, TSF- 333, BYK-307, BYK-377, BYK-UV3500 and BYK-UV3570 (manufactured by Big Chem Japan). These compounds may be used alone or in combination of two or more.

As the organosiloxane used in the present invention, the Hydrophile-Lipophile Balance (HLB) value is preferably 1 to 16, more preferably 3 to 14. If the HLB value is out of the above range, the stain on the adherend becomes poor, which is not preferable.

The pressure-sensitive adhesive composition may contain a polyoxyalkylene chain-containing compound that is a polyether compound (polyether component) that does not contain an organopolysiloxane. By containing the above compound in the pressure-sensitive adhesive, a pressure-sensitive adhesive excellent in wettability to the adherend can be obtained.

Specific examples of the polyoxyalkylene chain-containing compound containing no organopolysiloxane include, for example, polyoxyalkylene alkylamine, polyoxyalkylene diamine, polyoxyalkylene fatty acid ester, polyoxyalkylene sorbitan fatty acid ester , Nonionic surfactants such as polyoxyalkylene alkyl phenyl ether, polyoxyalkylene alkyl ether, polyoxyalkylene alkyl allyl ether, and polyoxyalkylene alkyl phenyl allyl ether; Anionic surfactants such as polyoxyalkylene alkyl ether sulfuric acid ester salts, polyoxyalkylene alkyl ether phosphoric acid ester salts, polyoxyalkylene alkyl phenyl ether sulfuric acid ester salts and polyoxyalkylene alkyl phenyl ether phosphoric acid ester salts; In addition, a cationic surfactant having a polyoxyalkylene chain (polyalkylene oxide chain), an amphoteric surfactant, a polyether compound having a polyoxyalkylene chain (and derivatives thereof), a polyoxyalkylene chain having a polyoxyalkylene chain (And derivatives thereof) and the like. Further, the polyoxyalkylene chain-containing monomer may be blended with the acrylic polymer as the polyoxyalkylene chain-containing compound. These polyoxyalkylene chain-containing compounds may be used alone or in combination of two or more.

Specific examples of the polyether compound having a polyoxyalkylene chain (polyether component) include a block copolymer of polypropylene glycol (PPG) -polyethylene glycol (PEG), a block copolymer of PPG-PEG-PPG, a block copolymer of PEG-PPG -PEG block copolymers and the like. Examples of the derivative of the polyether compound having the polyoxyalkylene chain include compounds having terminally etherified oxypropylene group-containing compounds (PPG monoalkyl ether, PEG-PPG monoalkyl ether, etc.), oxypropylene group-containing compounds (Terminal acetylated PPG and the like).

Specific examples of the acrylic compound having a polyoxyalkylene chain include a (meth) acrylate copolymer having an oxyalkylene group. When the ionic compound is used as the antistatic component, the oxyalkylene group is preferably 1 to 50, more preferably 2 to 30, And more preferably 2 to 20 carbon atoms. The terminal of the oxyalkylene chain may be substituted with an alkyl group, a phenyl group or the like as it is.

The (meth) acrylate polymer having an oxyalkylene group is preferably a polymer containing (meth) acrylic acid alkylene oxide as a monomer unit (component), and specific examples of the (meth) acrylic acid alkylene oxide include ethylene glycol (Meth) acrylate include methoxy-polyethylene glycol (meth) acrylate type such as methoxy-diethylene glycol (meth) acrylate and methoxy-triethylene glycol (meth) acrylate, ethoxy (Meth) acrylate type such as diethylene glycol (meth) acrylate and ethoxy-triethylene glycol (meth) acrylate, butoxy-diethylene glycol (meth) acrylate, butoxy- Polyethylene glycol (meth) acrylate type such as triethylene glycol (meth) acrylate, phenoxy-diethylene glycol (meth) acrylate, phenoxy Polyethylene glycol (meth) acrylate type such as triethylene glycol (meth) acrylate, 2-ethylhexylpolyethylene glycol (meth) acrylate, nonylphenol-polyethylene glycol And methoxy-polypropylene glycol (meth) acrylate type such as dipropylene glycol (meth) acrylate.

As the monomer unit (component), other monomer units (components) other than the (meth) acrylic acid alkylene oxide may also be used. Specific examples of other monomer components include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, s- Acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, (Meth) acrylate, n-decyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl Acrylate and / or methacrylate having an alkyl group having 1 to 14 carbon atoms such as methacrylate and methacrylate.

(Meth) acrylate, a phosphoric acid group-containing (meth) acrylate, a cyano group-containing (meth) acrylate, a vinyl ester, a carboxyl group-containing (meth) acrylate, (Meth) acrylate, epoxy group-containing (meth) acrylate, epoxy group-containing (meth) acrylate, amide group-containing (meth) Roile morpholine, vinyl ethers, and the like may be suitably used.

As a more preferred form, the polyoxyalkylene chain-containing compound containing no organopolysiloxane is a compound having at least a (poly) ethylene oxide chain. The blending of the (poly) ethylene oxide chain-containing compound improves the compatibility between the base polymer and the antistatic component, and preferably suppresses the bleeding to the adherend, thereby obtaining a pressure-sensitive adhesive composition of low staining property. Particularly, when a block copolymer of PPG-PEG-PPG is used, a pressure-sensitive adhesive excellent in low staining property can be obtained. As the polyethylene oxide chain-containing compound, the mass of the (poly) ethylene oxide chain occupying in the entire polyoxyalkylene chain-containing compound not containing the organopolysiloxane is preferably 5 to 90 mass%, more preferably 5 to 90 mass% 85% by mass, more preferably 5% to 80% by mass, and most preferably 5% to 75% by mass.

The number average molecular weight (Mn) of the polyoxyalkylene chain-containing compound containing no organopolysiloxane is suitably 50000 or less, preferably 200 to 30000, more preferably 200 to 10000, and usually 200 To 5,000 are suitably used. If Mn is larger than 50000, compatibility with the acrylic polymer is lowered, and the pressure-sensitive adhesive layer tends to whiten. If Mn is less than 200, contamination by the polyoxyalkylene compound tends to occur easily. Here, Mn refers to a polystyrene reduced value obtained by GPC (gel permeation chromatography).

Examples of commercial products of the above-mentioned organopolysiloxane-free polyoxyalkylene chain-containing compounds include ADEKA CLINIC 17R-4, ADEKA CLINIC 25R-2 (all of which are manufactured by ADEKA), LATEMUL EA-137, EA-157, EA-167, EA-167, EA-167 and EA- EA-177 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), and the like.

The content of the polyether compound is preferably from 0.01 to 3 parts by mass, more preferably from 0.03 to 2 parts by mass, still more preferably from 0.05 to 1 part by mass, most preferably from 1 to 3 parts by mass, relative to 100 parts by mass of the (meth) Preferably 0.05 to 0.5 parts by mass. Within the above range, it is preferable because it is easy to achieve both antistatic property and light fastness (re-releasability).

<Cross-linking agent>

In the surface protective film of the present invention, it is preferable that the pressure-sensitive adhesive composition contains a crosslinking agent. In the present invention, the pressure-sensitive adhesive composition is used to form a pressure-sensitive adhesive layer. For example, when the pressure-sensitive adhesive contains the (meth) acryl-based polymer, it is possible to appropriately adjust and crosslink the constituent unit, the constituent ratio, the cross-linking agent, and the addition ratio of the (meth) acryl- (Pressure-sensitive adhesive layer) can be obtained.

The crosslinking agent used in the present invention may be an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, a metal chelate compound, or the like. In particular, use of an isocyanate compound is a preferable form. These compounds may be used alone or in combination of two or more.

Examples of the isocyanate compound include aliphatic polyisocyanates such as trimethylene diisocyanate, butylenediisocyanate, hexamethylene diisocyanate (HDI) and dimeric acid diisocyanate, cyclopentylene diisocyanate, cyclohexylene diisocyanate, isophorone Alicyclic isocyanates such as diisocyanate (IPDI) and 1,3-bis (isocyanatomethyl) cyclohexane, alicyclic diisocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate (XDI), and aromatic isocyanates such as an isocyanate compound, an isocyanate compound such as an allophanate bond, a biuret bond, an isocyanurate bond, a uretdione bond, a urea bond, a carbodiimide bond, a uretonimine bond, Modified polyisocyanate can be used. SUMIDUR T80, SUMIDUR L, and DESMODUR N3400 (manufactured by Sumika Bayer Urethane Co., Ltd.), MILLIONATE MR (trade name, manufactured by Takeda Chemical Industries, Ltd.), TAKENATE D165N and TAKENATE D165N , MILLIONATE MT, CORONATE L, CORONATE HL and CORONATE HX (all manufactured by Nippon Polyurethane Industry Co., Ltd.). These isocyanate compounds may be used alone, or two or more isocyanate compounds may be used in combination, or a bifunctional isocyanate compound and a trifunctional or higher isocyanate compound may be used in combination. By using the crosslinking agent in combination, it is possible to obtain both a cohesive property and an anti-repulsion property (adhesion to a curved surface), thereby obtaining a surface protective film superior in adhesion reliability.

When the isocyanate compound (a bifunctional isocyanate compound and a trifunctional or higher isocyanate compound) is used in combination, the [bifunctional isocyanate compound] / [trifunctional or higher isocyanate compound] (Mass ratio) is preferably from 0.1 / 99.9 to 50/50, more preferably from 0.1 / 99.9 to 20/80, even more preferably from 0.1 / 99.9 to 10/90, even more preferably from 0.1 / 99.9 to 5/95 , And most preferably 0.1 / 99.9 to 1/99. By adjusting the content within the above range, a pressure-sensitive adhesive layer having excellent tackiness and resistance to repulsion becomes a preferable form.

Examples of the epoxy compound include N, N, N ', N'-tetraglycidyl-m-xylenediamine (trade name TETRAD-X, manufactured by Mitsubishi Gas Chemical Company) Diglycidylaminomethyl) cyclohexane (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Company).

Examples of the melamine resin include hexamethylol melamine and the like. Examples of the aziridine derivative include HDU, TAZM and TAZO (trade names, manufactured by Sogo Pharmaceutical Co., Ltd.) as commercial products.

Examples of the metal chelate compound include aluminum, iron, tin, titanium and nickel as metal components, and acetylenes, acetoacetates and ethyl lactates as chelate components.

The content of the crosslinking agent used in the present invention is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, per 100 parts by mass of the (meth) acryl-based polymer, more preferably 0.5 By mass to 10% by mass, and most preferably 1.0 to 6% by mass. When the content is less than 0.01 part by mass, the crosslinking formation by the crosslinking agent becomes insufficient, the cohesive force of the resulting pressure-sensitive adhesive layer becomes small, sufficient heat resistance can not be obtained, and tackiness residue tends to be a cause. On the other hand, when the content is more than 20 parts by mass, the cohesive force of the polymer is large, the fluidity is lowered, the wettability to an adherend (for example, a polarizing plate) becomes insufficient and the occurrence occurs between the adherend and the pressure- Which is a cause of blistering. Further, if the amount of the cross-linking agent is large, the peeling charging property tends to be lowered. These crosslinking agents may be used alone or in combination of two or more.

The pressure-sensitive adhesive composition may further contain a crosslinking catalyst for more effectively progressing any one of the crosslinking reactions described above. Examples of such a crosslinking catalyst include tin catalysts such as dibutyltin dilaurate and dioctyltin dilaurate, tris (acetylacetonato) iron, tris (hexane-2,4-diionato) Tris (heptane-2,4-dionate) iron, tris (heptane-3,5-dionate) iron, tris (5-methylhexane- (2,6-dimethylheptane-3,5-dionate) iron, tris (nonane-2,4-dioneato) iron, tris Iron, tris (nonane-4,6-dionate) iron, tris (2,2,6,6-tetramethylheptane-3,5-dionate) iron, tris (tridecane-6,8- Iron, tris (1-phenylbutane-1,3-dione) iron, tris (hexafluoroacetylacetonato) iron, tris (acetoacetic acid ethyl) (Isopropyl acetoacetate) iron, tris (acetoacetate Tris (acetoacetic acid-sec-butyl) iron, tris (propionylacetic acid methyl) iron, tris (propionylacetate) iron, tris Tris (propionylacetic acid-sec-butyl) iron, tris (propionylacetic acid-sec-butyl) iron, tris (propionylacetic acid- tris (tert-butyl) iron, tris (benzoyl acetoacetate), tris (dimethyl malonate), tris (diethyl malonate), trimethoxy iron, triethoxy iron, Iron-based catalysts such as iron can be used. These crosslinking catalysts may be used alone or in combination of two or more.

The content of the crosslinking catalyst is not particularly limited, but is preferably about 0.0001 to 1 part by mass, more preferably about 0.001 to 0.5 part by mass, per 100 parts by mass of the (meth) acryl-based polymer. Within the above range, the speed of the crosslinking reaction is high when the pressure-sensitive adhesive layer is formed, and the time for which the pressure-sensitive adhesive composition is used becomes long, which is a preferable form.

The pressure-sensitive adhesive composition may contain an acryl oligomer. The acrylic oligomer preferably has a weight average molecular weight (Mw) of from 1,000 to less than 30,000, more preferably from 1,500 to less than 20,000, and still more preferably from 2,000 to less than 10,000. The acrylic oligomer is a (meth) acrylic copolymer containing a (meth) acrylic monomer having an alicyclic structure represented by the following general formula as a monomer unit, and when used as an acrylic pressure-sensitive adhesive, functions as a tackifier resin, And is effective for suppressing the floating of the surface protective film.

CH ₂ = C (R ¹ ) COOR ²

[Wherein R ¹ is a hydrogen atom or a methyl group and R ² is an alicyclic hydrocarbon group having an alicyclic structure]

Examples of the alicyclic hydrocarbon group R ² of the above general formula include alicyclic hydrocarbon groups such as cyclohexyl group, isobornyl group, dicyclopentanyl group, dicyclopentenyl group, adamantyl group, tricyclopentanyl group and tricyclopentenyl group And the like. Examples of the (meth) acrylate ester having an alicyclic hydrocarbon group include cyclohexyl (meth) acrylate having a cyclohexyl group, isobornyl (meth) acrylate having an isobornyl group, (Meth) acrylic acid such as dicyclopentanyl acrylate. By having the acrylic oligomer having the monomer unit having an acrylic monomer having a relatively bulky structure as described above, the adhesion can be improved.

The blending amount of the acrylic oligomer is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 7 parts by mass, and most preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the (meth) acryl-based polymer , And most preferably 0.3 to 2 parts by mass. When the amount is used in the above range, the peeling force (adhesive force) to the adherend can be improved, and it is easy to suppress the floating, which is a preferable form.

The pressure-sensitive adhesive composition may contain other known additives, and examples thereof include powders such as lubricants, colorants and pigments, plasticizers, tackifiers, low molecular weight polymers, surface lubricants, leveling agents, antioxidants, A stabilizer, a light stabilizer, an ultraviolet absorber, a polymerization inhibitor, a silane coupling agent, an inorganic or organic filler, a metal powder, a particulate, a thin water or the like.

&Lt; Adhesive layer and surface protective film &

The surface protective film of the present invention is formed by forming the pressure-sensitive adhesive layer on a substrate. In this case, the pressure-sensitive adhesive composition is usually crosslinked after application of the pressure-sensitive adhesive composition. However, It is also possible.

The method for forming the pressure-sensitive adhesive layer on the substrate is not particularly limited. For example, the pressure-sensitive adhesive composition (solution) is coated on the substrate and the pressure-sensitive adhesive layer is formed on the substrate by drying and removing the polymerization solvent. Thereafter, curing may be performed for the purpose of adjusting the component migration of the pressure-sensitive adhesive layer and adjusting the crosslinking reaction. When the pressure-sensitive adhesive composition is applied onto a substrate to produce a surface protective film, at least one solvent other than the polymerization solvent may be newly added to the pressure-sensitive adhesive composition so as to be uniformly applied on the substrate.

As a method of forming the pressure-sensitive adhesive layer in the production of the surface protective film of the present invention, a known method used for production of pressure-sensitive adhesive tapes is used. Specific examples include extrusion coating methods such as roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, die coating and the like.

The surface protective film of the present invention is usually manufactured so that the thickness of the pressure sensitive adhesive layer is 3 to 100 占 퐉, preferably 5 to 50 占 퐉. When the thickness of the pressure-sensitive adhesive layer is within the above-mentioned range, it is preferable that a suitable balance between re-peeling property and tackiness is easily achieved.

The total thickness of the surface protective film of the present invention is preferably 8 to 300 탆, more preferably 10 to 200 탆, and most preferably 20 to 100 탆. Within the above-mentioned range, it is preferable because it is excellent in adhesive property (re-release property, adhesiveness, etc.), workability, and appearance. The total thickness refers to the sum of thicknesses including all layers such as a substrate, a pressure-sensitive adhesive layer, and an antistatic layer.

<Separator>

In the surface protective film of the present invention, it is possible to adhere the separator to the surface of the pressure-sensitive adhesive layer for the purpose of protecting the pressure-sensitive adhesive surface, if necessary.

As the material constituting the separator, there are a paper or a plastic film, but a plastic film is suitably used because of its excellent surface smoothness. The film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer, and examples thereof include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, A polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film.

The thickness of the separator is usually 5 to 200 탆, preferably 10 to 100 탆. Within this range, it is preferable that the bonding operation to the pressure-sensitive adhesive layer and the peeling workability from the pressure-sensitive adhesive layer are excellent. If necessary, the separator may be subjected to antistatic treatment such as releasing treatment with a silicone, fluorine, long chain alkyl or fatty acid amide releasing agent, silica powder or the like, a coating type, a kneading type or a vapor deposition type.

The optical member of the present invention is preferably protected by the surface protective film. Since the surface protective film is excellent in antistatic property and peeling electrification voltage stability over time, it can be used as a surface protective film (surface protective film) for processing, transportation, shipment, etc. Therefore, It is useful for protecting the surface. Especially, since it can be used for plastic products which are liable to generate static electricity, it is very useful for antistatic use in technical fields related to optical and electronic parts, in which static electricity is a particularly serious problem.

[Example]

Hereinafter, some embodiments of the present invention will be described, but the present invention is not intended to be limited to these embodiments. In the following description, &quot; part &quot; and &quot;% &quot; are on a mass basis unless otherwise specified. The amount (added amount) in the table indicates the solid content or the solid content ratio.

Each characteristic in the following description was measured or evaluated as follows.

&Lt; Measurement of weight average molecular weight (Mw)

The weight average molecular weight (Mw) was measured using a GPC apparatus (HLC-8220GPC) manufactured by Tosoh Corporation. The measurement conditions are as follows.

Sample concentration: 0.2 mass% (THF solution)

Sample injection amount: 10 μl

Eluent: THF

Flow rate: 0.6 ml / min

Measuring temperature: 40 ° C

column :

Sample column; TSKguardcolumn SuperHZ-H (1) + TSKgel SuperHZM-H (2)

Reference column; TSKgel SuperH-RC (1)

Detector: Differential refractometer (RI)

In addition, the weight average molecular weight was determined in terms of polystyrene conversion. When it is necessary to measure the number average molecular weight (Mn), it is measured in the same manner as the weight average molecular weight.

&Lt; Glass transition temperature (Tg) >

The glass transition temperature Tg (占 폚) was determined by the following formula using the following document values as the glass transition temperature Tgn (占 폚) of the homopolymer by each monomer.

1 / (Tg + 273) =? [Wn / (Tgn + 273)

Wherein Tg (占 폚) is a glass transition temperature of the copolymer, Wn (-) is a mass fraction of each monomer, Tgn (占 폚) is a glass transition temperature of the homopolymer by each monomer, n is a kind of each monomer .]

Literature value:

2-ethylhexyl acrylate (2EHA): - 70 ° C

n-Butyl acrylate (BA): 55 ° C

4-hydroxybutyl acrylate (4HBA): - 32 C

2-hydroxyethyl acrylate (HEA): - 15 C

Acrylic acid (AA): 106 DEG C

N-vinylpyrrolidone (NVP): 80 DEG C

Diethyl acrylamide (DEAA): 81 C

As literature values, reference is made to "Polymer Handbook" (John Wiley & Sons), "Synthesis, design and development of new applications of acrylic resin" (published by Central Management Development Center Press) and "Polymer Handbook".

&Lt; Measurement of surface resistivity &

The surface resistivity was measured according to JIS-K-6911 using a resistivity meter (Hirestor UP MCP-HT450 type, manufactured by Mitsubishi Chemical Corporation) under an atmosphere of a temperature of 23 캜 and a humidity of 50% RH.

The surface resistivity (Ω / □) measured on the surface of the antistatic layer in the present invention is preferably 1 Ω / □ in the environment directly exposed to fluorescent light (400 lux) at room temperature (23 ° C. × 50% RH) immediately after coating (UV irradiation) under an environment of 23 ° C × 50% RH (high pressure mercury lamp, cumulative light amount: 4000 mJ / cm 2, irradiation time: 30 seconds) under each condition, preferably less than 1.0 × 10 ^11, more preferably less than 5.0 × 10 ^10, more preferably less than 1.0 × 10 ^10. The surface protective film exhibiting the surface resistivity within the above range can be suitably used as a surface protective film used in, for example, processing or transporting articles such as a liquid crystal cell, a semiconductor device, and the like, which do not like static electricity. Immediately after the coating means that the antistatic agent composition (solution) is coated and dried to form the antistatic layer immediately after formation of the antistatic layer. Hereinafter, the same applies.

&Lt; Evaluation of printability (print adhesion) >

Printing was performed on the surface of the antistatic layer using an X stamper manufactured by Shachiha Co., Ltd. under a measurement environment of 23 占 폚 占 50% RH, cellotape (trade mark) Peeling at a peeling speed of 30 m / min and a peeling angle of 180 deg. Thereafter, the surface after peeling was observed with naked eyes, and when the peeling of 50% or more of the print area was judged as x (poor printability) and when 50% or more of the print area was not peeled off, Respectively.

<Measurement of Rear Peel Force>

The surface protective film according to each example was cut into a size of 70 mm in width and 100 mm in length, and the product name Cellotape (trade name) (24 mm width, rubber adhesive tape) manufactured by Nitto Denko Corporation, trade name No.31B Width, acrylic adhesive tape) was pressed on the antistatic layer (back surface layer) of the surface protective film at a pressure of 0.25 MPa and a speed of 0.3 m / min. The sheet was peeled off at a peeling speed of 0.3 m / min and a peeling angle of 180 degrees under the same conditions, and the peel strength (N / 24 mm: large cell tape or N / 19 mm: Large No.31B) was measured.

The back side peel force (N / 24 mm: large cell tape) in the present invention is preferably 1 to 15 N / 24 mm, more preferably 2 to 13 N / 24 mm, and still more preferably 3 to 10 N / to be. The back side peel force (N / 19 mm: large No.31B) is preferably 1 to 15 N / 19 mm, more preferably 2 to 13 N / 19 mm, and further preferably 3 to 10 N / 19 mm. If the rear surface peeling force is too light (too low), the surface protective film can not be removed because the pickup tape does not adhere to the back surface of the surface protective film. If the back surface peeling force is too high, It is difficult to detach it.

&Lt; Measurement of Slidability (Dynamic Frictional Force) >

The surface protective film was cut into a size of 70 mm in width and 100 mm in length, and was then bonded to an acrylic plate (trade name "Acrylite", thickness: 1 mm, width: 70 mm, length: 100 mm, manufactured by Mitsubishi Rayon Co., Ltd.). The back side (antistatic layer surface) of this test piece was placed on a smooth PET film held horizontally, and a load of 1.5 kg was placed on the test piece. The test piece with the load was placed on a tensile tester using a non-stretchable yarn, and the test piece was pulled horizontally under the conditions of a tensile speed of 300 mm / min and a tensile distance of 300 mm at a measurement temperature of 25 ° C to obtain an average value (n = 3).

The sliding property (dynamic friction force) N in the present invention is preferably 2 to 5, more preferably 2 to 4.8 or less, still more preferably 3 to 4.5 or less. Within this range, when handling an adherend having a surface protective film, the slipperiness of the back surface of the surface protective film (antistatic layer surface) is satisfactory, and compatibility with the back surface peeling force (adhesive force) Lt; / RTI &gt;

<Solubility (Appearance)>

The appearance change when the antistatic layer (back surface layer) of the surface protective film according to each example was wiped with 10 reciprocations with Bemcot (manufactured by Asahi Kasei Co., Ltd.) moistened with ethanol was visually observed to show the case where the antistatic layer was removed, Was evaluated as &quot; o &quot;.

<Solvent resistance (measurement of surface resistivity)>

The antistatic layer (back surface layer) of the surface protective film according to each example was wiped with 10 reciprocations with Bemcot (manufactured by Asahi Kasei Co., Ltd.) impregnated with ethanol, and a resistivity meter (manufactured by Mitsubishi Chemical Corporation) The surface resistivity was measured according to JIS-K-6911 using a HILESTAR UP MCP-HT450 type.

The surface resistivity (Ω / □) measured on the surface of the antistatic layer in the present invention is preferably less than 1.0 × 10 ¹¹ , more preferably less than 5.0 × 10 ¹⁰ , and still more preferably less than 1.0 × 10 ¹⁰ . The surface protective film exhibiting the surface resistivity within the above range can be used to wipe out the unevenness on the surface protective film, for example, so that even when wiped with ethanol, the surface resistivity can be suppressed to a low level, And can be suitably used as a surface protective film to be used in the processing or transporting process.

&Lt; Measurement of Polarizer Peeling Voltage (Polarizer Side) >

The surface protective film 1 according to each example was cut into pieces each having a width of 70 mm and a length of 130 mm to peel off the release liner. Thereafter, as shown in Fig. 2, an acrylic plate 10 (manufactured by Mitsubishi Rayon Co., Ltd.) (SEG1423DU polarizing plate, width: 70 mm, length: 100 mm) attached to a polarizing plate 20 (manufactured by Nitto Denko Corporation, thickness: 70 mm, length: 100 mm) 1 was protruded 30 mm from the end of the polarizing plate 20, and was pressed with a hand roller.

The sample was allowed to stand for one day under an environment of 23 ° C × 50% RH, and then set at a predetermined position on a sample fixing table 30 having a height of 20 mm. The end portion of the surface protective film 1 protruding 30 mm from the polarizing plate 20 was fixed to an automatic winder (not shown), and peeled off at a peeling angle of 150 ° and a peeling rate of 10 m / min. The electric potential of the surface of the adhered object (polarizing plate) generated at this time is measured by a potential meter 40 (gas type manufactured by the former company, type "KSD-0103") fixed at a height of 100 mm from the center of the polarizer 20 Polarizer peeling electrification voltage &quot; The measurement was carried out in an environment of 23 ° C and 50% RH.

After leaving for one month (30 days) under an environment in which fluorescent light (400 lux) directly touches at room temperature (23 ° C × 50% RH), as in "initial polarizer peeling voltage" And measured as "polarizer peeling electrification voltage after UV irradiation" after irradiation with ultraviolet rays (high-pressure mercury lamp, cumulative light amount: 4000 mJ / cm 2, irradiation time: 30 seconds) in an environment of 23 ° C × 50% RH , And these measurements were carried out in an environment of 23 ° C × 50% RH.

The polarizer peeling voltage is a peeling electrification voltage derived from the antistatic layer and the pressure-sensitive adhesive layer constituting the surface protective film of the present invention, and contributes to the antistatic property.

The polarizing plate peeling electrification voltage (kV) (absolute value, initial, time elapsed, all after UV irradiation) in the present invention is preferably 0.6 or less, more preferably 0.5 or less, and further preferably 0.4 or less. Within the above range, for example, damage to the liquid crystal driver or the like can be prevented, which is a preferable form.

&Lt; Measurement of Peeling Voltage on Film Side (Antistatic Layer Side of Surface Protection Film) >

The surface protective film 1 was peeled off from the surface of the polarizing plate 20 so that the peeling angle was 150 ° and the peeling speed was 10 m / min, similarly to the measurement of the polarizing plate peeling electrification voltage. The electric potential of the surface protective film 1 generated at this time is measured with a potential meter 40 (gas type manufactured by Kawasaki K.K., Ltd., type "KSD-0103") fixed at a height of 100 mm from the center of the surface protective film 1, &Quot; initial film side peeling electrification voltage &quot; was measured. The measurement was carried out in an environment of 23 ° C and 50% RH.

After leaving for one month (30 days) under an environment in which fluorescent light (400 lux) directly touches at room temperature (23 占 폚 占 50% RH), as in &quot; initial film- Side peeling electrification voltage &quot;, and after irradiation with ultraviolet light (high-pressure mercury lamp, integrated light amount: 4000 mJ / cm 2, irradiation time: 30 seconds) in an environment of 23 캜 x 50% RH, &Quot;, and these measurements were carried out in an environment of 23 캜 x 50% RH.

The film-side peeling electrification voltage is the peeling electrification voltage derived from the antistatic layer constituting the surface protective film of the present invention, and contributes to the antistatic property.

The film side peeling electrification voltage (kV) (absolute value, initial, time elapsed, all after UV irradiation) in the present invention is preferably 0.6 or less, more preferably 0.5 or less, and further preferably 0.4 or less . When the amount is within the above range, the surface protective film after peeling does not become electrified and the workability is excellent, which is a preferable form.

<Preparation of aqueous dispersion for antistatic layer A>

(Aqua-PASS, weight average molecular weight 40,000, manufactured by Mitsubishi Rayon Co., Ltd.) as a conductive polymer, and poly (3,4-ethylenedioxythiophene) (PEDOT) / polystyrenesulfonic acid (PSS) (Baytron P, H, C, Starck), an isocyanurate of hexamethylene diisocyanate blocked with diisopropylamine as a crosslinking agent, fatty acid 100 parts by mass of solid content of the binder, 80 parts by mass of polyaniline sulfonic acid as a solid fraction, 20 parts by mass of PEDOT / PSS as a solid fraction, and 20 parts by mass of a crosslinking agent were added to a mixed solvent of water / ethanol (1/1) 10 parts by mass as a solid fraction, and 10 parts by mass as a solid fraction were added, followed by stirring for about 20 minutes to sufficiently mix. Thus, an aqueous dispersion for antistatic layer A of about 0.4% NV was prepared.

<Preparation of aqueous dispersion for antistatic layer B>

(Aqua-PASS, weight average molecular weight 40,000, manufactured by Mitsubishi Rayon Co., Ltd.) as a conductive polymer, and poly (3,4-ethylenedioxythiophene) (PEDOT) / polystyrenesulfonic acid (PSS) (Baytron P, H, C, manufactured by Starck), methylol methylol melamine as a crosslinking agent, carbinol modified polydimethylsiloxane (BY16-201 , 100 parts by mass of solid content, 45 parts by mass of polyaniline sulfonic acid as a solid fraction, and 30 parts by mass of PEDOT / PSS as a solid fraction were mixed in a mixed solvent of water / ethanol (1/1) , 10 parts by mass of a crosslinking agent as a solid fraction, and 10 parts by mass of a lubricant as a solid fraction were added, followed by stirring for about 20 minutes to sufficiently mix. Thus, an aqueous dispersion for antistatic layer B of about 0.4% NV was prepared.

&Lt; Preparation of water dispersion for antistatic layer C >

(Aqua-PASS, weight average molecular weight 40,000, manufactured by Mitsubishi Rayon Co., Ltd.) as a conductive polymer, and poly (3,4-ethylenedioxythiophene) (PEDOT) / polystyrene sulfonic acid (PSS) (manufactured by Baytron P, H, C, Starck), isocyanurate of hexamethylene diisocyanate blocked with diisopropylamine as a crosslinking agent, and methoxy Methylolmelamine and a fluorine-containing block copolymer (Modifier F200, manufactured by NOF Corporation) as a lubricant were mixed in a mixed solvent of water / ethanol (1/1), 100 parts by mass of a binder in solid content, 100 parts by mass of polyaniline sulfonic acid , 25 parts by mass of PEDOT / PSS as a solid fraction, 10 parts by mass of each crosslinking agent as a solid fraction, and 10 parts by mass of a lubricant as a solid fraction were added, followed by stirring for about 20 minutes. Thus, an aqueous dispersion for antistatic layer C of about 0.4% NV was prepared.

<Preparation of aqueous dispersion for antistatic layer D>

(Aqua-PASS, weight average molecular weight 40,000, manufactured by Mitsubishi Rayon Co., Ltd.) as a conductive polymer, and poly (3,4-ethylenedioxythiophene) (PEDOT) / polystyrenesulfonic acid (PSS) (Baytron P, H, C, manufactured by Starck) as a cross-linking agent, carnauba wax as a lubricant as a lubricant, water / ethanol 100 parts by mass of solid content, 20 parts by mass of polyaniline sulfonic acid as solid content, 80 parts by mass of PEDOT / PSS as solid content, 10 parts by mass of solid content of crosslinking agent, 20 parts by mass of a solid portion was added, and the mixture was stirred for about 20 minutes to sufficiently mix. Thus, an aqueous dispersion for antistatic layer D of about 0.4% NV was prepared.

&Lt; Preparation of water dispersion for antistatic layer K >

(A copolymer of methyl methacrylate / n-butyl acrylate / cyclohexyl methacrylate = 6/2/1) as the binder, polyaniline sulfonic acid (aqua-PASS weight average molecular weight: 40,000, Mitsubishi Rayon Co., (PEDOT) / polystyrenesulfonic acid (PSS) (Baytron P, H, C, manufactured by Starck), and methyl methoxyl melamine as a crosslinking agent in water / ethanol (1 / 1), 100 parts by mass of a solid content of the binder, 25 parts by mass of polyaniline sulfonic acid as a solid fraction, 75 parts by mass of PEDOT / PSS as a solid fraction, and 10 parts by mass of a crosslinking agent as a solid fraction were added to a mixed solvent of about 20 The mixture was stirred for a minute and sufficiently mixed. Thus, an aqueous dispersion for antistatic layer K of about 0.4% NV was prepared.

<Preparation of aqueous dispersion for antistatic layers E to J>

An aqueous dispersion for antistatic layers E to J was obtained in the same manner as in the preparation of aqueous dispersions for antistatic layers A to D based on the compounding contents in Table 1.

<Preparation of aqueous dispersion for antistatic layer L>

(Aqua-PASS, weight average molecular weight 40,000, manufactured by Mitsubishi Rayon Co., Ltd.) as a conductive polymer, and poly (3,4-ethylenedioxythiophene) (PEDOT) / polystyrenesulfonic acid (PSS) (Baytron P, H, C, Starck), isocyanurate of hexamethylene diisocyanate blocked with diisopropylamine as a cross-linking agent, fluorine-based , 100 parts by mass of a solid content of a binder, 25 parts by mass of polyaniline sulfonic acid as a solid fraction, 5 parts by mass of a PEDOT (trade name, manufactured by Mitsui Chemicals, Inc.) / PSS in a solid amount of 25 parts by mass, a cross-linking agent in a solid fraction in an amount of 10 parts by mass, and a lubricant in a solid fraction in an amount of 170 parts by mass, followed by stirring for about 20 minutes. Thus, an aqueous dispersion for antistatic layer L of about 0.4% NV was prepared.

<Preparation of aqueous dispersion for antistatic layer M>

(Weight average molecular weight: 15,000, manufactured by Aldrich), and poly (3,4-ethylenedioxythiophene) as a binder (trade name: PEDOT) / polystyrenesulfonic acid (PSS) (Baytron P, H, C, manufactured by Starck), methoxymethylol melamine as a crosslinking agent, and carnauba wax as a wax activator were mixed with water / ethanol (1/1) 100 parts by mass of solid content of the binder, 10 parts by mass of polyaniline as a solid fraction, 90 parts by mass of PEDOT / PSS as a solid fraction, 10 parts by mass of a crosslinking agent as a solid fraction, and 20 parts by mass of a lubricant as a solid fraction were added to the solvent And the mixture was stirred for about 20 minutes and sufficiently mixed. Thus, an aqueous dispersion for anti-static layer M of about 0.4% NV was prepared.

<Preparation of acrylic polymer 1 for pressure-sensitive adhesive layer>

100 parts by mass of 2-ethylhexyl acrylate (2EHA), 4 parts by mass of 2-hydroxyethyl acrylate (HEA), and 2 parts by mass of a polymerization initiator were added to a four-necked flask equipped with a stirrer, a thermometer, 0.2 part by mass of 2'-azobisisobutylonitrile and 157 parts by mass of ethyl acetate were introduced and nitrogen gas was introduced with gentle stirring to carry out the polymerization reaction for 6 hours while maintaining the temperature of the liquid in the flask at around 65 DEG C, To prepare a polymer 1 solution (40 mass%). The acrylic polymer 1 had a weight average molecular weight of 540,000 and a glass transition temperature (Tg) of -68 ° C.

<Preparation of acrylic polymer 8 for pressure-sensitive adhesive layer>

100 parts by mass of 2-ethylhexyl acrylate (2EHA), 10 parts by mass of 4-hydroxybutyl acrylate (4HBA) and 0.02 part by mass of acrylic acid (AA) were added to a four-necked flask equipped with a stirrer, a thermometer, , 0.1 part by mass of N-vinylpyrrolidone (NVP), 0.2 part by mass of 2,2'-azobisisobutyronitrile as a polymerization initiator, and 157 parts by mass of ethyl acetate were introduced and nitrogen gas was introduced with gentle stirring , And the polymerization reaction was carried out for 6 hours while maintaining the temperature of the liquid in the flask at around 65 DEG C to prepare an acrylic polymer 8 solution (40 mass%). The acrylic polymer 8 had a weight average molecular weight of 540,000 and a glass transition temperature (Tg) of -67 ° C.

<Preparation of acrylic polymer 2 to 7, 9 and 10 for pressure-sensitive adhesive layer>

Acrylic polymers 2 to 7, 9 and 10 were obtained in the same manner as in the acrylic polymer 1 or 8 for the pressure-sensitive adhesive layer. The components other than the monomer component were the same as those of the acrylic polymer 1.

&Lt; Preparation of acrylic pressure-sensitive adhesive 1 solution for pressure-sensitive adhesive layer &

The acrylic polymer 1 solution (40 mass%) was diluted to 20 mass% with ethyl acetate, and 500 mass parts (solid content 100 mass parts) of this solution was added with an isocyanurate of hexamethylene diisocyanate (Nippon Polyurethane Industry Co., 3.5 parts by mass (solid content: 3.5 parts by mass) of CORONATE HX: C / HX) and 3 parts by mass (solid content: 0.03 parts by mass) of dibutyltin dilaurate (1% by mass ethyl acetate solution) Followed by stirring to prepare a solution of the acrylic pressure-sensitive adhesive 1.

<Preparation of acrylic pressure-sensitive adhesive 10 solution for pressure-sensitive adhesive layer>

An organopolysiloxane (KF-353, manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved in 500 parts by mass (solid content: 100 parts by mass) of the acrylic polymer 10 solution (20 mass% a solution of 2 parts by mass was diluted with 10% (solid content: 0.2 parts by weight), lithium bis as an alkali metal salt antistatic component (trifluoromethane sulfone) imide (LiN (CF ₃ SO _{2) 2:} LiTFSI, Tokyo chemical Industry Co., Ltd. preparation ) As a crosslinking agent (1.0 part by mass) as an isocyanate compound of hexamethylene diisocyanate (CORONATE HX: C / HX manufactured by Nippon Polyurethane Industry Co., Ltd.) as a crosslinking agent (Solid content: 1.0 part by mass) and 0.3 part by mass (solids content: 0.3 part by mass) of 1,3-bis (isocyanatomethyl) cyclohexane (TAKENATE 600 manufactured by Mitsui Chemicals, Inc.), iron (III) acetylacetonate % Ethyl acetate solution) 0.5 parts by mass (solid 0.005 parts by mass) was added and mixed and stirred to prepare a solution of the acrylic pressure-sensitive adhesive 10.

&Lt; Preparation of solution of acrylic pressure-sensitive adhesive 2 to 9 for pressure-sensitive adhesive layer &

A solution of the acrylic pressure-sensitive adhesive 2 to 9 was obtained in the same manner as the acrylic pressure-sensitive adhesive 1 or 10.

<Preparation of urethane-based pressure-sensitive adhesive 11 solution>

85 parts by mass of PREMINOL S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000) as a polyol having three hydroxyl groups, 13 parts by mass of SANNIX GP3000 (manufactured by Sanyo Chemical Industries, Ltd., Mn = 3000), which is a polyol having three hydroxyl groups, 2 parts by mass of SANNIX GP1000 (manufactured by Sanyo Chemical Industries, Ltd., Mn = 1000) having three polyols, 18 parts by mass of an isocyanate compound (CORONATE HX: C / HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) 0.04 part by mass of acetonate (manufactured by Tokyo Chemical Industry Co., Ltd.) and 210 parts by mass of ethyl acetate as a diluting solvent were blended to obtain a urethane pressure-sensitive adhesive 11 solution. In addition, as a raw material for the urethane pressure-sensitive adhesive solution, all materials except for the solvent are 100% concentration.

&Lt; Preparation of urethane pressure-sensitive adhesive 12 solution >

A urethane pressure-sensitive adhesive 12 solution was obtained in the same manner as in the above urethane pressure-sensitive adhesive solution 11 except that 0.08 parts by mass of tin dilaurate of a tin catalyst was used as a catalyst.

&Lt; Preparation of urethane pressure-sensitive adhesive 13 solution >

Except that 30 parts by weight of isopropyl myristate (EXCEPARL IPM, manufactured by Kao Corp.) as a wettability improving agent and 0.5 part by weight of Irganox 1010 (manufactured by BASF) as an antioxidant were further blended, 13 solution.

&Lt; Preparation of urethane pressure-sensitive adhesive 14 solution >

0.1 part by mass of a polyether compound (KF-6004, manufactured by Shin-Etsu Chemical Co., Ltd.), 1-ethyl-3-methylimidazolium bis (fluorosulfonyl) imide (EMIFSI, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) ) Was further blended to obtain a urethane pressure-sensitive adhesive solution (14) in the same manner as the urethane pressure-sensitive adhesive solution (13).

&Lt; Preparation of solution of silicone adhesive agent 15 >

100 parts by mass of solid content, &quot; CAT-PL-50T &quot; (manufactured by Shin-Etsu Chemical Co., Ltd.) as a platinum catalyst, 0.5 part by mass of X-40-3229 (solid content 60% 100 parts by mass were added to obtain a silicone-based pressure-sensitive adhesive 15 solution.

&Lt; Preparation of solution of silicone adhesive agent 16 >

Polyether-based compound (KF-353, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.2 mass parts (methanesulfonyl trifluoromethyl) anti-static component, lithium bis-imide _{(LiN (CF 3 SO 2)} 2: LiTFSI, Tokyo Chemical Industries Co. ) Was further blended in the same manner as in the above silicone-based pressure-sensitive adhesive 15 solution.

<Preparation of antistatic layer-adhered base material>

(A) to (K) was dried on a transparent polyethylene terephthalate (PET) film (polyester film) having a thickness of 38 탆, a width of 30 cm and a length of 40 cm, . This coating material was heated at 130 캜 for one minute and dried to prepare an antistatic layer-attached base material having an antistatic layer on the first surface of the PET film.

&Lt; Example 1 >

&Lt; Preparation of surface protective film >

The acrylic pressure-sensitive adhesive 1 solution was coated on the opposite side of the antistatic layer of the substrate having the antistatic layer (antistatic layer-attached substrate) and heated at 130 캜 for 1 minute to form a pressure-sensitive adhesive layer having a thickness of 15 탆. Subsequently, a silicone-treated surface of a polyethylene terephthalate film (thickness: 25 mu m), which is a separator subjected to a silicon treatment on one surface, was laminated on the surface of the pressure-sensitive adhesive layer to prepare a surface protective film.

&Lt; Example 11 >

&Lt; Preparation of surface protective film >

A solution of the urethane pressure-sensitive adhesive 11 was coated on the surface opposite to the antistatic layer of the base material (antistatic layer-adhered base material) having the antistatic layer and heated at 130 占 폚 for 1 minute to form a pressure sensitive adhesive layer having a thickness of 10 占 퐉. Subsequently, a silicone-treated surface of a polyethylene terephthalate film (thickness: 25 mu m), which is a separator subjected to a silicon treatment on one surface, was laminated on the surface of the pressure-sensitive adhesive layer to prepare a surface protective film.

&Lt; Example 15 >

&Lt; Preparation of surface protective film >

The silicone-based pressure-sensitive adhesive solution 15 was coated on the opposite side of the antistatic layer of the base material (antistatic layer-attached base material) having the antistatic layer and heated at 150 占 폚 for 1 minute to form a pressure sensitive adhesive layer having a thickness of 10 占 퐉. Subsequently, a silicone-treated surface of a polyethylene terephthalate film (thickness: 25 mu m), which is a separator subjected to a silicon treatment on one surface, was laminated on the surface of the pressure-sensitive adhesive layer to prepare a surface protective film.

&Lt; Examples 2 to 10, Example 17, Example 18 and Comparative Examples 1 to 5 >

A surface protective film was prepared in the same manner as in Example 1, based on the blending contents in Tables 1 to 3.

&Lt; Examples 12 to 14 >

A surface protective film was produced in the same manner as in Example 11, based on the blending contents in Tables 1 and 4.

&Lt; Example 16 >

A surface protective film was produced in the same manner as in Example 15, based on the blending contents in Tables 1 and 5.

Table 6 shows the results of various measurements and evaluations of the surface protective films according to Examples and Comparative Examples.

The abbreviations in Tables 2 and 3 will be described below. The abbreviations in the other tables are based on the examples.

[Monomer component]

2EHA: 2-ethylhexyl acrylate

BA: n-butyl acrylate

4HBA: 4-hydroxybutyl acrylate

HEA: 2-hydroxyethyl acrylate

AA: Acrylic acid

NVP: N-vinylpyrrolidone

DEAA: diethylacrylamide

[Polyether compound]

KF353: organopolysiloxane having an oxyalkylene chain (HLB value: 10) (trade name: KF353, manufactured by Shin-Etsu Chemical Co., Ltd.)

KF6004: organopolysiloxane having an oxyalkylene chain (HLB value: 9) (trade name: KF-6004, manufactured by Shin-Etsu Chemical Co., Ltd.)

HS10: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name "Aquaron HS10" (anionic surfactant)

EA137: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name "NOIGEN EA-137" (nonionic surfactant)

[Antistatic component (ionic compound)]

LITFSI: Lithium bis (trifluoromethanesulfonyl) imide (alkali metal salt, manufactured by Tokyo Chemical Industry Co., Ltd.) (active ingredient 100%)

BMPTFSI: 1-butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) imide (liquid liquid, liquid phase at 25 占 폚 manufactured by Sigma Aldrich)

EMIFSI: ionic liquid: 1-ethyl-3-methylimidazolium bis (fluorosulfonyl) imide (ionic liquid, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)

[Crosslinking agent]

C / HX: Isocyanurate of hexamethylene diisocyanate (trade name: CORONATE HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) (100% active ingredient)

C / L: trimethylolpropane / trilene isocyanate (trade name: CORONATE L, manufactured by Nippon Polyurethane Industry Co., Ltd. (active ingredient 75%))

TAKENATE 600: 1,3-bis (isocyanatomethyl) cyclohexane (trade name: TAKENATE 600, manufactured by Mitsui Chemicals, Inc.) (100% active ingredient)

[Crosslinking catalyst]

Sn: Dibutyl tin dilaurate (dibutyl tin dilaurate) (manufactured by Tokyo Chemical Industry Co., Ltd.)

Fe: tris (acetylacetonato) iron (iron (III) acetylacetonate) (manufactured by Tokyo Chemical Industry Co., Ltd.)

Note) "> 1E + 13" in the table indicates that the 13th power of 10 is exceeded.

From Table 6, it can be seen that, in all the examples, when the ionic compound and the polyether compound as the antistatic agent are mixed together, the polarizing plate peeling electrification voltage is excellent and the electrification preventing layer It was confirmed that the slip property was excellent when the lubricant was mixed with the lubricant, and that when the antistatic component was added to the pressure-sensitive adhesive layer, the polarizer peeling electrification pressure was also excellent. In addition, in Example 17 using a polyester resin, it was confirmed that the resin composition was also excellent in the solvent resistance as compared with Example 17 using an acrylic resin as a binder.

On the other hand, from Table 6, it can be seen from Table 6 that the conductive polymer constituting the antistatic layer was not blended in a desired ratio, and that the surface resistivity and the film-side peeling electrification voltage after UV irradiation were lower than those in Examples . Particularly, in Comparative Example 5, since an external dope type polyaniline was used in place of the self-doping type polyaniline sulfonic acid having conductivity itself, polyanions (PSS) from polythiophenes (PEDOT) ), And it was confirmed that the surface resistivity with time lapsed compared to the example.

Industrial availability

The surface protective film disclosed herein can be used for manufacturing optical members used as components of a liquid crystal display panel, a plasma display panel (PDP), an organic light emitting diode (EL) display and the like, It is suitable as a protective film. In particular, a surface protective film (surface protective film for optical use) applied to an optical member such as a polarizing plate (polarizing film) for a liquid crystal display panel, a wavelength plate, a retardation plate, an optical compensation film, a brightness enhancement film, a light diffusion sheet, .

1: Surface protective film
10: Acrylic plate
20: polarizer
30: Sample Stands
40: Potentiometer
11: Antistatic layer
12: substrate
13: Pressure-sensitive adhesive layer

Claims (11)

A surface protective film comprising a substrate having a first side and a second side, an antistatic layer formed on the first side of the base, and a pressure-sensitive adhesive layer formed on the second side of the base with a pressure-
Wherein the antistatic layer is formed from an antistatic agent composition containing a polythiophene doped with a polyaniline sulfonic acid and a polyanion as a conductive polymer component and a binder,
Wherein the mixing ratio (mass ratio) of the polyaniline sulfonic acid to the polythiophenes doped with the polyanions is from 90:10 to 10:90.
The method according to claim 1,
Wherein the polythiophene is poly (3,4-ethylenedioxythiophene) (PEDOT).
3. The method according to claim 1 or 2,
Wherein the polyanions are polystyrenesulfonic acid (PSS).
4. The method according to any one of claims 1 to 3,
Characterized in that the binder is a polyester resin.
Surface protection film.
5. The method according to any one of claims 1 to 4,
Wherein the antistatic agent composition comprises a melamine crosslinking agent and / or an isocyanate crosslinking agent as a crosslinking agent.
6. The method according to any one of claims 1 to 5,
Wherein the antistatic agent composition comprises at least one member selected from the group consisting of a fatty acid amide, a fatty acid ester, a silicone lubricant, a fluorine lubricant, and a wax lubricant as a lubricant.
7. The method according to any one of claims 1 to 6,
Wherein the substrate is a polyester film.
8. The method according to any one of claims 1 to 7,
Wherein the pressure-sensitive adhesive composition comprises at least one member selected from the group consisting of an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, and a silicone pressure-sensitive adhesive.
9. The method according to any one of claims 1 to 8,
Wherein the pressure-sensitive adhesive composition comprises a polyether compound.
10. The method according to any one of claims 1 to 9,
Wherein the pressure-sensitive adhesive composition comprises an antistatic component. An optical member characterized by being protected by the surface protective film according to any one of claims 1 to 10.

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